L.H.
SAME problem! Oh my goodness, I was at my wit's end with night-time wake ups or early morning ones; love my little guy, but I need my sleep :) I hated the Huggies overnights as while they would sop up the pee, they got hard and inflated, ultimately waking my daughter up since she was like a weeble by morning! NO fun :) . So when this started happening with my son, we tried the newly released Pampers Ultra-Absorbancy kind. What a LIFESAVER these have been. They hold way more urine than a typical diaper (as evidenced by the nights my husband forgets to put him in one and we have a wake up call way too early!) but they don't expand or get hard the way the Huggies do. They're pricey, and while you get what you pay for we use them only for night-time or for naps and buy them at BJ's where it's cheaper (bonus: this month's BJ's Journal has a SEVEN dollar coupon just for the super absorbancies! I've contacted every family/friend who I know won't use them and have a whole stack to use! woo hoo!)
Hope this helps,
L.
p.s. they come in the bigger sizes ~ my little tank (26.5 pounds) just turned 1 on Wednesday and we have him in size sixes at night. Next he'll be in Depends :)