Well, to be particular, its the blend of beliefs she was given by her Parens, which is a bit of a hodge-podge of Catharism, Dark Gnosticism, and Luciferianism. She wants to create an item because she knows that the world is run by a cruel, wicked, and capricious God, the same one who once turned the world upside down by kicking out his most humble servant Lucifer for no good reason, thus proving himself unfit to rule.
God created everything and is part of everything. Therefore he created the snake in the garden, including its intentions to share knowledge of good and evil with humanity, so they would know how not to offend God During the fall, God was actually part of adam, eve, the serpent, and the apple. They committed no crime, but if they did, God was their partner in crime. Yet he punished all the criminals except himself. Everyone else has "done their time." It is God's turn to be subject to his own judgement.
She doesn't "trust God" (aka dice), so she wants an item.
She wants it to affect multiple people, so it will not only help her during any difficult moments in her pregency and delivery, but also help her twins survive after they are born.
After that, she'll be done with it. By gifting it to the covenant, she got others to help pay for the cost, AND appears altruistic and kind.
Just because she's an infernalist doesn't mean she's out of the closet (yet) and she finds that acts of charity help to quell rumors. The new "Hospital of St. Paul" should do nicely in that regard.
Injured Grogs who recover there might feel a "debt of gratitude" and who doesn't like to have people in their debt.
Just because she's a witch doesn't mean she rides around on a broom cackling "I'll get you, my pretties." That is such a stereotype.
Straightforward? Have you been following this thread, or any threads for that matter? 
One simple question, 2 pages of responses, and we're now debating whether or not you can walk into/out of a circle if its installed on the roof and you've dropped your Parma.
I honestly wonder how anyone ever actually plays this game. After the last session descended into serious arguing over lab creation rules, I introduced a new house rule:
"If you ask for a short explanation of my reasoning in interpreting a rule, I'll give it. If you then further argue against my interpretation, I'll get up out of my chair, put my dog in my place, and go sit outside reading some light fiction until there is no more argument. You can try to convince my dog all you want, but as you all know, she is tough to sway and unlikely to give into your arguments."
The rule seems to have gone over well, but I think my players thought I was joking. I'm not.