I have a dcb and he was in size 6 pampers at 10 months old ....about 6-8 months ago mom was worried that he was going to grow out of them before being trained (he's currently 22.5 months) so mom bought pullups for him and what I found was they don't really keep the wet away from the skin like a diaper ..but that's their purpose ...when you are using pull ups yyou want the kid to feel wet so they know they went right? so when the boy got up from nap his skin was damp and being prone to rashes I suggested we just muscle along as best we can with the size 6 diapers ....he has gone on a growing spurt ...upwards not outwards thankfully....and they are still fitting him....so maybe put a plastic pants on over the diaper and hope as he progresses from walking to running he will slim down a bit ...