I had no idea that flying squirrels were nocturnal. As a kid, my father found a baby flying squirrel in his fur lined boot. We kept it in a bird cage and fed it milk with one of my dolls baby bottles, then peanut butter/fruits and finally released it when it was healthy enough. He/She would come to my window to eat the peanut butter we left for it outside on the sill. This was during the day. Every now and then we saw it flying around the trees in the woods next to our house.