Sweating toddler?

bee • ♥️💙

LO is on the chunky side he’s a overall clammy sweaty kid (especially at bed) and he is in the process of potty training however just recently weather has been super high and he’s been scratching his butt! His but is super moist in the diaper however he’s not wet and he’s will scratch until he bleeds. I’m hoping to speed up the potty process but it’s doesn’t feel like it’s happening. I’ve cut his nails super short and I even let him air out or wear underwear. Any clues to help !?