My 2.5 month old daughter has started leaking pee through her diaper. It's not every time, but it's starting to happen once per day. We use Pampers Pure and she's wearing a size 1 (she's 12lbs). She's at the weight where the size 2 diapers start, however her size 1's don't seem too small. When I change her diaper I'm able to have the fasteners touch so it's tight enough on her without being too tight. My daughter is a heavy pee-er, but when she's leaked it's not even that her diaper is soaked or heavy. I'm stumped...I feel like if I go up a size it would fit kind of loose since the size 1's still fit. Any other babies having this issue?