I can think of off the top of my head
Les Miserables (3 kids... one little boy and two little girls, but one doesn't sing)
The Boy From Oz (Peter Allen as a kid)
Miss Saigon (one little boy... but he doesn't sing and he is Kim and Chris's son)
Lion King (Simba and Nana? Both have solos... obviously Simba more)
NIL MAGNUM NISI BONUM "No greatness without goodness."
RENThead, enLIGHist, Ozalot, Grobanite, Ringer, Pickwick LW, Wicked, Lost, American Dreams, West Wing
Lea S. Hugh J. Adam P. Idina M. Matt M. Taye D.