Sounds good. It was a really long thread, which is what justifies 15xp in my mind.
If there are no objections I'm gonna add this to Cecilio's history. It kind of slipped and never got added, but its suddenly important.
Family: Cecilio's family's Gift seems to have a weird quirk in that it is inherited by daughters. Cecilio, the Elder's mother was Gifted. As was her mother. And so on until at least the first one to be a member of the Order. They do have male children of course, but they aren't Gifted and with the Order's general culture they often end up forgotten when talking about family history, and the family has developed a thread of pride about their quirk. Cecilio the Younger's mother and grandmother both let their sons be raised by the father without paying them much mind. In addition to Cecilio the Younger's grandmother, and mother she has a living sister and great aunt. The sister, Artemis, recently passed her Gauntlet, the great aunt is crazy and near twilight, the mother has started sending letters hinting at children and the grandmother is sending letters asking when she will she her great granddaughter.
It's my understanding that the Gift is very, very, very rarely hereditary (at least to any extent that anyone can prove). Even House Mercere, which claims that its Gift is hereditary has a very low success rate. Having an unbroken line of Gifted mothers/daughters that went back many generations would seem to be extraordinarily remarkable, if not unprecedented. And having multiple family members gifted (mother, sister, grandmother, and great aunt) seems also not in keeping with the way I understand magi work in Mythic Europe. There just aren't that many magi for five in three generations to be possible.
Again, that's my understanding, which might be flawed.
Ars Magica has a number of families where the gift is hereditary- a hedge tradition somewhere and Mercere before he lost the Gift. it is certainly not the norm however. I think part of the issue pre-parma would be finding two mages who could stand each other long enough to have a child. Female-only lines of Gifted are more common, and one could hypothesize that it was tied to a property of their breast milk rather than heredity...
I know the books have a handful of exceptions. Like that one guy from Guardian's of the Forest (pg 50) Petrus. I think there is another one in magi of hermes, at least according to the Apprentice's book. But that's the general rule more or less.
Actually, Apprentices explicitly states that the "norm" (ie. RAW) for Ars Magica is that the Gift is NOT hereditary. It then goes on to mention two exceptions; the guy from Guardians of the Forest and the one in Magi of Hermes as QPaC pointed out. So, it's obviously not unheard of, but also exceptionally rare and definitely cause for a reputation of some sort. I'd almost like to say that their should be a virtue or possibly Story Flaw associated with it (ie. Cecilio is constantly hounded by magi or even covenfolk to have a child with them because of her family's unique trait).
Either would make sense. If its a story flaw it would have to be minor IMO, but I already have one. Hmm... I haven't used self-confident mechanically speaking. Could I swap that out for a virtue?
Keep Self Confident. It is the single best Virtue in the game.
The rules do not say you cannot have more than one Story Flaw. It says "should not", which leaves plenty of wiggle room.
I have stated in discussion, nd it is in the HR's, that I allow 2 Story Faws as long as only one is Major. I allow 3 Personality Flaws, again only one Major. I am also amicable to the idea of treating almost any Story Flaw as Major or Minor.
But whatever it may be, these limits apply to your initial balance. Events and Mysteries and such can break limits. For Example, Roberto has Mentor, always has. It has played a larger role in past games. When he hooked up with the Princess, he gained the Gentle Gift and True Love. So he has currently 2 Story Flaws, one Minor and one Major.
As for the Gift, it is not hereditary. There are exceptions and it does hapen from time to time that a magus has a gifted child. But this is too inconsistant and unpredictable.
Right, the question was if Cecilio and her family could be one of the exceptions?
Ahem...
That is a sexist load of malarkey. So, No. Just no.
Meh. To call it a Story Flaw sets the precedent that potential are ultra rare, something I don't think any of us would like. And really? What kind of story will we get out of that. As a Virtue, maybe. But all it does is grant you a potential apprentice, presuming you catch with child someday. No guarentee. And are potential apprentices really so ultra rare? More rare than magi? I would think the opposite. Trained magi are more rare than other Gifted individuals.
The more I think about it, the more I really don't care. So I will cop out and say to let the Troupe decide. But I ask you this and that...
- Why? How does it accenctuate or enhance the character? To say it is in your family background is one thing. Tales can be exaggerated or fabricated or have a mystery untold behind them. And we do not need to define the exact traits of anyone's ancestor.
- If it is yoour goal as a player to have a maga character which gives birth to a Gifted child, we can work on that individually rather than defining a Virtue or Flaw others can take or defining a new HR that others can use. I would rather play with inconsistant superstition and guess worl. Make a story out of it. Perhaps team up with Fleur and her project in hopes of reaping the benefit of her using Fertility Magic to grant you a Gifted child should you ever catch.
- Do you have a father in mind? Or an idea of what sort of man you would like him to be? Fathers are very important on many levels, both realistic and mythic. Mothers are important, equally so but not more so.
'Nuff Said.
Consider as you will and get the troupe to decide. I have had my say and I wash my hands of it.
We have seen only two exceptions in the canon to the rule that the Gift is not hereditary. One is a single magus who's children are all Gifted, and one is a family in which every seventh son is Gifted. I think the jury's still out on whether the Gift is hereditary in House Mercere. It certainly seems rare enough there, and is nowhere near consistent. All that can really be said is that certain abilities seem to be hereditary among those who are Gifted in House Mercere - a slightly different proposition.
If Cecelio's family bred true in the female line such that every daughter was Gifted, they would be the single most noteworthy and exceptional bloodline in the history of the Order of Hermes since, well, since ever. While the first two exceptions bend the rule that the Gift is not hereditary, this would push it to the breaking point. And it makes me wonder just what Marko does - how does this enhance the character?
What's more, it cheapens other characters. Fleur is designed to be a maga who makes a breakthrough in fertility magic that allows Gifted children to be made more predictably. In my mind this is a Big Deal, and should be a hermetic breakthrough of a significant level. Can it be done? Sure. Should it be easy? No. But it's a great hermetic project to devote years of study and research to. To have Cecelio's family already do naturally what Fleur is trying to do with fertility magic makes Fleur's efforts seem a little less spectacular in my view. It seems a better story to me if her breakthrough is just that, a breakthrough.
Also, Lucas is from a family (House Mercere) that prides itself on having magi 'in the family.' I had him be of House Mercere, marry early, and have four kids before LR in the hope that one of them might be Gifted. (No luck so far.) It seems kind of unfair for another player to be able to just declare that her daughters will all (all!) have the Gift. Could I simply declare that one of Lucas's kids has developed the Gift?
I tend to agree with Marko on this. We have a maga addressing this very issue. If Cecelio wants a Gifted child, maybe she could work with Fleur to get one. I certainly have the idea that if one of my kids can't be Gifted, maybe one of my grandkids (or great-grandkids) can through Fleur's efforts. I figure by the time she's experimenting on those kind of fertility treatments, Lucas's kids (or grandkids) will be just about the right age...
In any case, I have nothing against people carving out their own story in the saga, and even having that story be spectacular. But I'd prefer that the story not upend the background principles on which the game is based.
Four. Ex Miscelania (I believe, it may have been elsewhere) mentions a hedge tradition which is matrilineal where all the daughters have the gift. Also it is made clear that all of Mercere's children had the gift until he lost the gift himself. How that relates to the lineage of the current mercer magi is unclear...
Trogdor, you and Marko have very nearly convinced me, on making it a goal/legend. I do still want my character to have blood/familial ties in the Order, and have a Gifted child. Of course as Marko pointed legends are just legends. Any complaints about improbability might be solved by copious use of Homunculi, ReMe on an unlucky infernalists and/or miracles. The only thing with working with Fleur is I don't want to step on silveroaks toes. Silveroak, team research project? Would that be okay with you?
A partner for working on making gifted children, how could Fleur say no?
I'm assuming you are wanting to work on fertility magic together is the game plan here...
If you're in need of a male volunteer, Lucas has a son who'll be just about the right age in a few years.... 
Huzzah! Good thing I have this convenient experiment focused lab. I'll post a revised family history soonish.
What you could maybe do is have a line of gifted maga, but not from mother to sister.
Something like
Maga A has 2 sisters
3 daughters, 6 nieces.
7 granddaughters (disregarding the sister's line at this point)
19 grand-grand-daughters.
One of her niece gets the gift, she takes her as an apprentice.
And when one of her grand-granddaughter happens to have it, she's taken in by the niece.
So we have a family, where, disregarding the men, we have at least 38 women, on 4 generations, 3 of them being maga, with a parens-filia line.
This seems enough to get a reputation for being a gifted family, yet it could totally be random chance and doesn't get overboard, IMO
Here was going to be the new family "tree"/history:
Cecilio, the younger has an identical Gifted twin sister. To avoid being overstressed with teaching or being overly unfair fosterage and relative time rate trickery was used. Cecilio was born first by a few minutes, but due to her closer relationship with the Queen of Blood and Ice and Sand time ended up going slower for her, so by amount of time lived she's the younger one. That plus the Unaging granted by the Queen mean Cecilio looks much younger than her sister. Her Cecilio's mother and great aunt are Gifted as well, as were many of the woman up Cecilio's family line. Supposedly, the family was originally a hedge tradition where a daugher always inherited the Gift from their mothers, but its unclear if this was due to the hedge tradition or some quirk of the Gift or something else entirely. Whatever the case its not that way now, since the blood line has been cut via adoption and there are many elaborate stories about how they have gotten the Gift in the past. Cecilio the Elder's father supposedly prayed for 40 days and 40 nights for a miracle to grant her the Gift. The great aunt supposedly has her Gift granted by a Faerie Homunculus which has been in the family since time began. Other stories invovle trips to the magic realm, enslaving infernalists, consuming large amounts of vis during the pregnency, wishes from genies and so forth. Most people dismiss it as crap.
The upshot of this is that the Gift isn't hereditary, and she has a family.
Great Aunt of Celcio the Younger, Agathe is a powerful maga with a questionable grasp on reality. She confuses people with other people, is currently researching a way to transmute turnips to vis and is seaking a red vegtable to create artifical plant hearts. She saw it in her dreams. She's mostly harmless. She is less than subtle in encouraging
Grantfather of Celcio the Younger, Adam. Supposedly a Holy Hermit wandering aimlessly and dispensing advice and healing. He's heretical and routinely has to flee from the Church. Cecilio the Younger has seen very little of him. But writes him letters when she needs spiritual advice. Its not entirely clear how he gets the letter after it is handed off to a Redcap, but he usually writes a reply eventually. The time to get a reply can range from as soon as she sends it to up to a decade.
Cecilio's sister, Abbie. A animal loving maga who's current research goal is finding a way to breed magical creatures without vis. Otherwise they'll be killed for their vis, a clear unacceptable result. Spoils Purity when she shows up. Distrusts the Queen. Even though they were born on the same day, Cecilio's time in Faerie means Abbie has lived about a decade longer. She looks like an older ear and tail free version of Cecilio. Some people will confuse them for daughter and mother.
This seem more reasonable?
IMO, that's the problem.
Dilute that, like I suggested above. Instead of "Many of the women from her family are gifted", take "All gifted women from her line come from the same family".
This means that instead of having, say, 12 living maga from the same family (Which is a great political AND magical force), you've got 3 of them, which is already very unusual: The gift manifests in what? 1 person out of 10 000? I don't remember exactly.
Oh, now we're talking 
I agree, she could come from a power-mad family that deals with anything that grants power. So you could have, say, 5-6 living relative with the gift, 3 of them False, 2 homunculy, with Cecilio maybe being the only "true" gift.
I'm still wary of having an entire family line with lots of people having access to large sources of huge power. That phrase evoques the kind of things that even the mercere can't easily do.