The adult stage often lasts until the Tamagotchi turns ten. The Tamagotchi will then turn into an oldie. An oldie will remain on a Tamagotchi toy until it dies or returns home. Oldies can mate with oldies of the opposite gender to produce babies. On certain Tamagotchi versions, the mating of Otokitchi and Ojitchi will produce Oyajitchi (or on the Tama-Go, Tamagotchi iD, and TMGC+C, Grippatchi).