I was talking with my care-giver about it last night. She had been talking with my ex about, and about how long Middle Son's nails are (which was something we talked with his teachers about at school last week). The care giver said that normally she's opposed to sedatives, but in Middle Son's case she thought it was worth talking to his doctor and getting a prescription so that we could do "hygiene day" every 2-3 months.
I think that is a good idea. I can usually manage to trim his finger nails without a big struggle. Toe nails are harder. And frankly, I'm not sure I can cut his hair safely any more.