K.P.
Shannon,
i'm only a few months late with some advise but hope it'll come in handy. My 21 month old son is in size 6 diapers, i found size 5 he was leeking out of. He's not a big boy, about 33 lbs., 34" tall. But at night i put a sanitary napkin inside his diaper. I use a thick one to help absorb the wetness. When he wakes up, he's soaked, but most of the time has not leaked thru.