May I suggest that even though some of these child actors have grown up to be great adults in films, that we forget what they became (or didn't) and concentrate on the child they were below the age of 14. May I also suggest you list one movie that child was in.

Here goes:

Jean-Pierre Leaud - The 400 Blows
Brandon de Wilde - Member of the Wedding; Shane
Hayley Mills - Tiger Bay; Whistle Down the Wind
Roddy McDowall- How Green Was My Valley
Elizabeth Taylor- National Velvet
Judy Garland - The Wizard of Oz
Freddie Bartholomew - Captains Courageous; David Copperfield
Victoire Thivisol - Ponette
Kate Maberly - The Secret Garden (1993)
Margaret O'Brien - Meet Me in St. Louis
River Phoenix - Stand By Me
Wil Wheaton - Stand By Me
Pelle Hvenegaard - Pelle the Conqueror

There are so many others. Help me fill them in.

Sara