Well, mine are 2 years apart and although they get along well enough and like to play when they both have the energy, I think it might be different if they were littermates. The only time they touch when resting or sleeping is when they are in the car and there is no room for the doggy equivilant of "personal space" when not in lockdown in their carseats. At home when sleepy, its always in allignment with plenty of space between. Of course if its cold when we lower the heat they will curl up, but never together. On the other hand, they LOVE to be next to a human when trying to sleep
