S1·E49 Kitten Smitten

Heathcliff learns that playing Momma Cat is no easy task after he is adopted by a tiny kitten lost from her mother. Heathcliff teaches the little girl all about life as they roam the streets together in search of the missing mom, and they soon become fast friends. Heathcliff's big responsibility ends when at last the mother and kitten are reunited, but a touching moment at the end reveals that Heathcliff is really going to miss the little thing.