Pokémon Season 5 Episode 12

With the young Lugia in the possession of Butch and Cassidy, Ash and friends set about rescuing it while protecting its parent from itself. The parent Lugia fights desperately to free its child—playing right into Team Rocket’s hands. If Ash fails to win the Lugia’s trust and convince it not to oppose Team Rocket alone, it seems this Pokemon is fated to end up in captivity along with its child.