S.S.
I know those diapers say like 16 to 28 lbs, but I've found when you get that when you get within 5 lbs of the max, it may be time to go up a size.... don't know why but that seems to help. Also, try the night-time diapers if you can find them (sometimes they are hard to find) they work well...also limiting drinks at bedtime helps as well.