What kind of fit are they?? My thinking is that if they are a little baggy in the crotch area that could lead to bunching? I've only used my GK on bubs and he's 12 weeks so I'm not experienced with a pocket on a toddler. But on him I can see (obviously) it is saggy in the crotch so I try to shorten the rise as much as possible to keep that whole crotch area as taut as I can, iykwim? I dunno, could be way off here....