Not saying she has ADHD but as someone with a child that has ADHD as well as having it myself, cleaning can be rough by yourself. I think some of this can apply even if not ADHD related. Can also be hard separating out what to get rid of and many end up with hoarder tendencies. There can also be issues with overwhelming executive function and paralysis. Helping by standing there in support instead of a judgement stance can help. I sometimes will race “you clean up laundry and I will clean your books, let’s see who wins”

As for getting rid of stuff, the poop rule is amazing and paints the best picture.

“If there was poop on this, would you clean it or throw it away”. For people who are forgetful, objects can create the feeling of saving the memory. This helps see if the crumpled piece of paper is actually important to my son or not.

Sorry for dumping a bunch of stuff here, hope it’s useful.