I can't help you with the soft towels- mine are soft, but I'm not sur they count as "fluffy soft"...however, I do NOT ues hot water in my wash...anyway- do you have a washer/dryer in our house? or are you going out to do it? I'm not sure given your "lug up and down the steps" part.
If your going out to do it- I cant help.
HOWEVER I will say that my DD7 & 8 do their fare share of laundry. DD8 can and does run both the washer/dryer at times. DD7- is still in training.
They each have a hamper by the washer/dryer. When their clothes come out of the dryer- they are put back in their hamper. These are NOT folded! I bring the hampers up to their rooms and put them in the doorway. They then fold/hang up all of their clothes, and put the hamper back down at the washer/dryer
I have a small basket that I toss their socks into- that gets put in the living room 1x a week- usually on Sundays- and they go through them and match their own socks and put them away
sheets are washed on Mondays now (use to be sunday, for some reason I changed) They get out of bed, and instead of making it, they strip it and throw it down to the washer/dryer. After school on Monday- before supper, they remake their own beds.
My girls are both younger than yours- I think you could enlist your DD's help in laundry!
And for the record- DH does laudnry here too...especially now that the wood stove is going- when he loads it, he'll swap the washer/dryer he folds and puts away too...just not quite as "good" as I do, so I try to do that myself, or just live with his towels folded the WRONG way in my linen closet LOL
Brandy