If you would stat out the powers, I'll assign personality and copy to my main sheet.
Why teaching 7 for the cat? To the suspicious in me, it looks like you want it to teach Fleur stuff really fast and overcome her lower starting skill base. It might not be the case, but this is what it looks like.
I have found very liitle in the cat's backstory that implies that he is a master teacher at all, even if his abilities and virtues make him such a thing. I fact I find his hermetic MT to be quite high as well. The MT of old mages is mostly superseded with more modern knowledge, I would say, that MT is something you need to keep constantly updated. A Magic Lore of 7 would be better I would say 
He picked up a lot of teaching while being taught a lot. He may have been asked to help teach apprentices in the past as well.
The cat may or may not have ever existed before Fleur. It thinks it did though, and imagines a long history with magi of the past. The truth of this is irrelevant. The cat simply is, and is what it is supposed to be, which is a Magical Animal Companion. Not yet a Familiar, but potentially so at some point. The Story Flaw aspect will remain though.
In other words, I do not mind if the cat is custom designed to fit Fleur's needs. She is twenty years behind most magi, 15 years behind Roberto and 5 years behind Vibria who has a dragon family.
Having said that, I did warn silveroak to try to fly under the radar. Stacking it with a high Com score and Good Teacher results in a potential Source Quality of 20. And the cat can teach how to Teach. And the ritual power has me leery because I suspect you are going to permanently grant virtues to people. However, that bit seems to be okay with the other players. The teaching stack is causing a radar blip.
I know it is hard to make everybody happy. I had to take some hits with Roberto, even lowering scores earned in a previous saga he was in. So I sympathize, and offer a compromise. Choose one: the power to grant a Virtue or the super teaching stack.
OR...
A deal I have always offered when there are disagreements.
Get two other players to put their stamp of approval on things.
But for the most part I think Fleur is great 
I'm fine with a Grant Minor Virtue Ritual Power, as long as there's not a reduced Might cost for making it Permanent, and if it either must rest for five seasons in a Magic Aura of at least 3 (with "rest" having the same or similar restrictions as recovering from a major injury) or consume 65 pawns of Vis to recover its lost Might Score.
Ritual Powers also allow you to spend Confidence points instead of Might (page 40, middle column, last paragraph). It seems to imply that you have to have enough points on hand to pay the whole of the cost, not a mix.
Then again, confidence points are hard to come by.
Does that count as Peregrin's stamp of approval? I'm not sure at what point I would need to start figuring out what to replace the ritual power with...
People like the ritual power, so keep it
I am not trying to nay say you. I often let all sorts of things slide. I just want to address concerns of other players. And really, the one and only thing that caused a radar blip is the Teaching super stack.
My offer was an example of me being shiesty 
Everyone seems to like the power, so keep it. Peregrine and Fixer both stated appreciation for it. Get two players to approve of the Teaching super stack, and we are good.
Which actually brings up something I've been thinking about- part of the reason I initially went with the teaching was to have the cat teach languages. Now the cat has gift of tongues instead, and I wonder if it can still teach languages if there are fluent speakers around. For example, if Fleur spent a season in Barcelona, she could normally get 8 pts of language experience in Spanish. Could she instead be taught Spanish by the cat to learn the language more quickly?
Also once she has the cat as a familiar, and an apprentice, the cat can teach her apprentice additional seasons (though obviously not in arts) while Fleur does things like read...
I have no problem with the teaching stack, because the cat's abilities are not that high and are limited in scope. You need to convince Xavi.
And the answer to the Language Question is NO. What is going on is that, whatever language you hear sounds in your mind like your native tongue. Whenever you speak your native tongue, in the ears of others it sounds like their native tongue. There are some words that just translate as "meow" though
You can only teach languages you actually know, and if you are speaking in a language that is not your native tongue, then those words are not translated.
And none of this applies to reading. You also have to actually know the language to read & write in it. Gift of Tongues offers no help nor hindrance.
It would be Catalan, not Spanish but hey. For starters Spanish does not exist at the time, basically because Spain does not exist either and will not exist for 270 years. Then, Spanish is only made into the vehicular language in the late XIXth century. before that, after 1714, it is implemented as the official administrative language. So, as you see a far off event all in all. Right now it is Catalan in Barcelona.
Why don't you skyrocket a few abilities and drop some points in teaching? Teaching does not seem central to the character cncept, while broad worldly experience is, so high area lores organization lores, academic and supernatural lores would be top notch for him, but he looks like having weird ideas at the same time, so maybe he is not that good at communicating them?
Xavi is right. I am using the anachronistic terms Spanish and Catalan when the more accurate terms would be Castilian and Occitan. I use the term Spanish to group together Castilian with similar forms of Latin being spoken in Leon and Aragon, which are distinct from Galician and Occitan. But it is an analogue spectrum. Castilian is evolved from Leon, Leon shares traits with Galician (aka Portuguese), Aragonese has similarities to Catalan. Castilian of the day is not the same as Castilian spoken today, and as a form of Gothic Latin, it shares traits with Italian of the day.
Or so they say. I am basing this all on the writings of philologists. I speak English, a tiny amount of Spanish, and an even tinier amount of Greek. Catalan is a new flavor I am exploring
Is gat pronounced as "gaat" or "ghat" or "gaht"?
Yeah, I originally gave her teaching 7 with no good teacher virtue, with the virtue I think this makes more sense:
Characteristics:
Int 1 Per 1
Pre -2 Com 3
Str -7 Sta 0
Dex 3 Quick 4
Qualities
gift of speech (minor 1)
Personal power :hands of the magical animal (minor1)
vis sourcex2:creo (minor 2)
Ritual power:grant minor virtue(second sight) (major3)
improved confidence (minor 2)
susceptible to deprivation (minor -1)
reduced attack (claws) (minor -1)
reduced damage (claws) (minor -1)
improved characteristics (minor 2)
Personal power :gift og the frog's legs (minor 1)
reduced abilities (minor -2)
Gift of Tongues (minor 1)
educated (minor 1)
improved powers (minor 1)
Flaws
magical freind(minor-1)
nocturnal(minor-1)
craving for travel(minor-1)
greedy(major-3)
delusion(minor-1)
Virtues
perfect balance(minor+1)
Puissant Awareness(minor+1)
sharp ears(minor+1)
unaffected by the gift(minor+1)
good teacher(minor+1)
second sight(minor+1)
arcane lore(minor+1)
Abilities
cat speak 5
athletics 3
awareness 4
brawl 3
stealth 4
hunt 4
artes Liberales 5
Latin 5
Second Sight 5
leadership 4
guile 4
magic theory 5
magic lore 4
Faerie Lore 4
Finesse 5
Teaching 4
Order of Hermes Lore 7
Classic Greek 5
Philosophae 4
hedge witch magic theory 2
intrigue 4
area lore -Marseille 3
area lore -Doisettep 3
area lore -Andorra 3
I would give him more magic lore and less hermetic theory, but that is me. What about some broader area lores? he has been around for a while, after all, so I would say thatr 2 or 3 tribunals at 3-4 or so would be OK.
I've already put 1200 points into abilities and you are suggesting it needs more?
Considering she needs a source quality above 13 to learn anything I think she is doing quite well...
I am suggesting you move XP around to grant him those. Maybe dropping some of the other area lores and downgrading other abilities to increase area lores and some of the lores.
I think the abilities he has now work better for him. He has a desire to be a traveler, but due to restrictions in terms of how long he can be outside of a magic aura, those have not been as widely realized as the area lores you propose would suggest.
Where did the cat get Andorra Lore from?
If you drop that and lower Magic Theory one point, that gives you 55xp to redistribute in a way that makes Xavi comfortable. However, MT is not a big deal to me because it is lower than Fleur's score, and Fleur is a long way off from training an apprentice. She might try the Boni-snatch, but with her low level of experience and accomplishment, she would cause bad waves doing that so soon.
What if we change Area Lore Andorra to Area Lore Rhine Tribunal?
Works for me.
OR...
You could take Area Lore - Pyrenees 
That includes a major part of the Provencal Tribunal as well as Andorra.
OR
You could take Mythic Europe Lore