Keira was famously quite young when she broke out: She was 17 when Bend It Like Beckham hit theaters, and was 18 in Love Actually. But she had been acting for nearly a decade before that: Her first role was in Screen One in 1993. Here she is in her second credited role in The Bill (1995), at 10 years old:
Sophie Marceau - 14 years old in "la boum"
and
Natalie Portman - 12 years old in Léon