Can one wash clothes on chol hamoed along with a load of laundry that they are doing for a baby?
No you may not add regular clothes to the wash.
Can a housekeeper do laundry during chol hamoed? clothing for adults? sheets and towels?
Towels are ok. You can never have enough of those.
Sheets you should try to have enough not to need a wash. Same goes for adult clothing.
Are you referring to kitchen or bath towels or are both ok?
If adult clothing gets dirty on chol hamoed may it be washed together with other clothing?
Yes, If don’t have more clothes