We have a heating pad we turn on in the late fall through early spring for the feral cats and kittens when the nights get cold. Bond discovered the heating pad when it was empty last night, and laid on it. Several of the youngest kittens found the heating pad and the warm bond, so Spook (the dark kitten) laid beside Bond, and one of Cute Nose's kittens was laying behind bond (the grey in front of the dark pillow behind them).