Motto! Ojamajo Doremi Kaeru Ishi no Himitsu(2001)

Motto! Ojamajo Doremi Kaeru Ishi no Himitsu

Mo~tto Ojamajo Doremi movie features the five witches Doremi, Aiko, Hazuki, Onpu, and Momoko as they visit Doremi's grandpa's home. There, they learn of the mystery of the frog stone, a magical place where magic used to mingle in the old countryside. Aiko rediscovers her love for grandpa, and Doremi learns a piece of the magical kingdom's past.

(Source: Anime News Network)