Mama wa Shougaku 4 Nensei  

Mama is a 4th Grader, Mama wa Shougaku Yonensei, ママは小学４年生, Mama wa Shougaku 4-nensei

Due to her father's job assignment in London, 4th-grade student Natsumi had to relocate from Japan. Her classmates threw a farewell party for her before she left. Although Natsumi was ready to go to London, an unexpected event occurred on the night before her departure. A baby appeared at her home after a thunderstorm, and it turned out that this infant would be the one Natsumi would give birth to in fifteen years!