Jungle Taitei - episode 13 - 28 Dec, 1965

With Roger (Kenichi) longing for human company, Kimba (Leo) and the other animals form a chorus to revive his spirits. But their singing summons Viper Snakely (Hamm Egg) and Tubby (Kutter), who are on yet another hunting expedition, to their location, and upon recognizing his father's slayers, Kimba must decide whether or not he wishes to seek revenge for his parents' deaths. (Source: IMDb)