Sea Otters hold hands when they sleep. This is a natural instinct called "rafting" that keeps them from drifting away in rough waters. A raft typically contains 10 to 100 animals. The largest raft ever seen contained over 2000 sea otters!
A sea otter mother is devoted to her pups and will take care of orphans. She wraps the baby in kelp when it sleeps, and cradles it on her chest to keep it warm. Mothers have been known to carry a pup for days even after it dies :(
Watch this cute video from Vancouver zoo: Otters holding hands #ValentinesDay