A Chipmunk Reunion

Alvin, Simon and Theodore argue about the exact date of their birth, a detail none of them (or Dave) can confirm. Dave celebrates their birthday on the day he found them, which only adds to the confusion. The argument hints at a deeper longing for a real family history.

Alvin declares that the only way to learn the truth about their birth is to find their long-lost mother. The others consider the dangerous idea, torn between curiosity and safety. The resolve sets the adventure in motion.

Dave discovers the boys have already left to look for Vinny and immediately decides to join them, bringing the Chipettes along. They head toward the forest to pursue the mystery together. The small group shifts from a family disagreement to a rescue mission.

While the search continues, the brothers imagine what their mother might be like and pursue answers from forest animals, though luck is scarce. Alvin grapples with the ache of feeling abandoned. The journey keeps their hopes and fears in tension.

The boys decide to head back, but a wild boar crashes the moment, chasing them into a hollow log. The log is hurled down the mountainside, leaving the boys unconscious. The forest becomes eerily quiet as danger closes in.

Someone discovers the unconscious boys and carries them to Vinny's dwelling. They awaken later inside their mother's home, stunned to be reunited with Vinny. The moment marks a turning point from fear to family.

The next morning, the boys wake up under Vinny's watchful care and are thrilled to see their mother again. Vinny expresses warmth and relief at their return. The family begins to heal past wounds.

Vinny reveals the harsh reasons for giving them up: winter was too cruel and food was scarce. She also shares that she knew Dave, a man kind to the forest animals, would take care of them if given the chance. Her confession complicates the boys' feelings about her absence.

The boys decide Vinny should come to live with them, but she admits she doesn't know how life in the city would suit her. Alvin, who doesn't want to leave Dave behind, distances himself emotionally. Simon and Theodore try to comfort him and keep hope alive.

The boar returns and rams Vinny at the cliff's edge, injuring her badly. She loses her balance and kicks off toward the river; the boar tumbles into the water and drowns. The boys rush to their mother, fearing the worst.

The brothers bring Vinny home, tend her wounds, and apologize for their earlier resentment. The accident deepens their understanding of Vinny's love and sacrifice. Bonds begin to mend as they accept her presence.

The next day, Vinny and the others orchestrate a surprise party for the boys. Dave and the Chipettes, exhausted, do their best not to disturb them. The brothers rush to hug Dave and promise to return with him, with plans to visit the forest.

That night, back at their city home, the brothers celebrate with a final scene of love and laughter. Alvin shares that his birthday wish has shifted: he now understands they have parents who love them very much. The family settles in, grateful for their bond.