Which is why you flat iron their hair. The flat iron kills the eggs. If you've removed all the live lice then there are none to lay more eggs.Then you can take your sweet time picking nits or just leave them.
And there is some serious overkill going on with the laundry. And major mis-information on where lice live. They live on human heads ONLY. They don't want to go on your stuffies, your couch, etc. They stay on your head. Doing a quick vacuum(in case one has lost it's way) and running everything non-washable through the dryer on high heat (heat kills them), is sufficient. Water can't 'drown' them or else they'd drown on your head.
So stop wasting water. Pop the stuffies in the dryer on high heat. Same with the pillows/pillowcases.