"Bear had a gift for making everything better."
The tree has lost its leaves because it is winter and Ren is sad. Bear postpones his hibernation and the two friends enjoy a joyous day of fun in the snow. That night they are joined by mouse who invites them to play a game of star catching.
Eventually bear must sleep but before he heads off into his cave he has a special idea which will transform the tree.
I will quote one more line from this exquisite and gentle book :
"Bear offered Ren his umbrella and they sat, as they often did, for as long as was needed"