We have the same problem. Cooper has *always peed through his night night diaper. We use Luvs during the day and Pampers at night and move up in sizes frequently. We had NO luck with Huggies.

His mattress is plastic so, honestly, I just change his sheet and matress pad (a folded up king sized sheet or towels) every day. I am just kinda over getting annoyed now. There isn't a gd thing to do about it.