The two cubs – Otto and Rollo – were in a tree, as usual.  But their behavior was not the ordinary.  See how they jockeyed for position and started in separate parts of the tree but ended up very much together.

Rollo was above Otto, with space between them.

Otto decided to get closer to his buddy.

Otto came very close to Rollo.

Otto tucked himself in just below Rollo.

Rollo seemed content. He wasn’t bothered at all.

The two cubs fell asleep together.

It is obvious that these two cubs have bonded.  They behave like siblings, although they are not related.