Not much is known of her except she was married to a firefighter.
Appearing briefly in the start of the series, she was worried that Aoba would be late for school. After Aoba arrives in the future, Aoba implied his sister could be alive but he had no hope for their mother still being alive. She also appears in one of Aoba's flashbacks, at the funeral of her husband, hugging Tsubasa.
Her status in 2088 is unknown, though she likely died of old age.