Quoting Levi and Brooklyn's Mommy:" I think I bought 2 boxes and about 5 big packs of nb diapers for dd, she was 7 lbs 12oz and was in them ... [snip!] ... 7 lbs 12oz and was in them for 2 1/2 months. When we ran out of those I just went to size 1 but they were still a little big. "
My DD weighed the same as yours at birth...and she's been in size 1 since she was a week and a half old lol. It's amazing how different babies are shaped, just like adults! I could wear a size 10 jeans and weigh the same as my mom and she could be in an 8. You just never can tell until you actually have the baby in front of you which diapers and clothes are going to fit and for how long. My DD wears plain white Gerber onesies in size 0-3 months, but they're getting small on her already. Yet, the colored onesies with the prints and embroidery (same brand, mind you) in size 0-3 months are still pretty loose on her and will probably fit for awhile. Some newborn clothes are way too small on her now, and others still fit (and are quite roomy) in the same size. So weird lol.