Grandpa and Grandma Turn Young Again

Grandpa, Grandma, and Winter Break (1x11)

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As the year draws to a close, the Saitou family prepares for their New Year's celebrations, which keeps Shouzou and Ine very busy. On the last day of the year, the whole family, including Ine's older sister, Tsuru, gathers at Shouzou and Ine's house.