Fullmetal Alchemist - The Armstrong Children

I wonder why Cathrine isn't performing the family pose that has been passed down through the generations? Is her being the youngest just mean she hasn't had time to fully learn and master the art or it could also be a right of passage in the family when they reach a certain age or goal, like a bar mitzvah with poseing

Catherine appeared in the old anime, she had a piano, and she used it to exercise.