Gym, or amusement park?

Our neighbors have a young tree in their backyard, and it has become the playground of our two young squirrels. The tree's branches are not stiff yet, so when a squirrel jumps on one it dips nearly to the ground and then springs up past full height. As you can probably imagin, the sight of two squirrels racing around chasing each other on such a tree is quite hilarious. The tree is dipping and swooning, and birds are scattering everywhere! Every-so-often a squirrel goes flying through the air and grabs a branch on his way by, only to have the same action repeated by the other squirrel going in the other direction. :)