Re: Favorite doublers? Or rip out soakers?
I recall both of my kids outgrowing the absorbency of the smalls around that age. They were able to fit into the mediums, though (and they were not large babies at all) and those were absorbent enough. They could fit in either the smalls or mediums, and after a month or so I could use smalls again b/c their peeing settled back down.
If the mediums don't work, I'd try putting in different inserts.