Brie showed up on Hollywood's radar with her role in Short Term 12, but she had been acting long before that. One of her first roles was at age eight, in a sketch on The Tonight Show with Jay Leno where she played a girl in a fake commercial for a "Roadkill Easy Bake Oven." Of course, Brie is super famous now that she's playing Captain Marvel in the MCU.
Sophie Marceau - 14 years old in "la boum"
and
Natalie Portman - 12 years old in Léon