Heather and her mom always do laundry on Thursday nights.  Every Thursday, they start with gathering all the dirty clothes from the hampers in each bedroom, and bathroom. Then, they put them into a larger basket and bring them to the laundry room.  They sort the clothes carefully into three main piles : colors, whites, and darks.  Sometimes there is a fourth pile, it is for delicates.    After they sort these clothes, they put in the first pile of clothes along with detergent, into the washer and turn the washing machine on.  They pick the water temperature they want, and let it wash those clothes.  After the first load is done, they put it into the drier. They start another wash load as the first one is drying.  They keep doing this until all the clothes piles are washed and dried.  They fold all the clothes, and put them in the rooms they came from for the other kids to put them away.
When did they start folding clothes?