8 month old peeing through diaper

As the title states…

My baby boy has peed through diapers before but I’ve attributed it to user error since he has become quite wiggly. Even though it’s happened before, it wasn’t happening daily or even weekly. But recently, he’s been peeing through diapers almost daily. Today it’s happened FOUR times. My mom was watching him while I worked from home so we both changed diapers today and it happened to both of us. I am now washing his crib bedding for the second time today.

He’s currently in size 4 and using Huggies little movers and size 4 overnights. I’ve also tried Huggies size 5, but those were the 360 line and the same thing happened. I figured it happened with the size 5s bc they’re too big. Idk how much he weighs right now bc he hasn’t seen the doctor since his 6 month visit where he weighed 19lbs.

I always fluff the leg ruffles, point his penis down, check the waistband. Everything! I’m at a complete loss for why this continues to happen.

Any advice on what my issue could be or what I should do? Thanks in advance!