Boo-Boo Bear is Yogi Bear's best friend and the deuteragonist in Yogi Bear animated series. Boo-Boo is a naive and mischievous bear who tries (usually unsuccessfully) to keep Yogi from doing things he should not do, and also to keep Yogi from getting into trouble with Ranger Smith.
At the beginning of Yogi Bear meets Josh he acted jealous as he thought Yogi was paying too much attention to Josh. However at the end when he revealed who Josh was,Yogi was very concerned as Josh and Boo Boo were heading towards a cliff. Often he would say "But Yogi, Mr. Ranger isn't gonna like this," or some variation. It is not readily apparent whether Boo-Boo is a juvenile bear with a precocious intellect or simply an adult bear who is short of stature.
However, in the episode "Cub Scout Boo-Boo", Yogi tries to persuade Boo-Boo to become a Boy Scout, and it appears that Josh likes the idea as he qotes "That`s a great idea,I m-m-mean, really?. Boo-Boo declines the offer, but Yogi corrects him by saying that he will be joining the "Cub Scouts", which Boo-Boo accepts,much to Josh and Yogis liking..
In Yogi Bear live-action/CGI film, Boo-Boo is the tetartagonist.