Misuzu had a bad relationship with her mother and ran away to Tokyo at age of 18.
She returned to her mother's place only once, with her then 4 year old daughter, who she left to live with her mother. Misuzu promised to Nana to come back for her, but broke that promise. Nana was fully adopted by her grandmother and never saw her mother ever again, even when Miyuki died.
Journalists from SEARCH found Misuzu and revealed that Nana's mother is living ordinary life as a housewife with husband and two children. She refuses to acknowledge any connection with Nana.
In response to learning who her mother is, Nana shows little emotional reaction, being only mildly disappointed at how ordinary her mother is, and still apparently unaware that the real Misato Uehara is her half-sister.
When her relationship to Nana Osaki is publically exposed, Misuzu flees from her family in Osaka. When Kurada tracks her down and implies that Misato is in danger after running away to Tokyo, Misuzu reluctantly reveals that she abandoned Nana because she wanted to be with a man who hated children. Afterward, she attempts to have her stepson to bring Misato home and is forced to do so herself when he refuses, because he wants her to take responsibility for her actions.
Misuzu is a middle aged but still beautiful woman. She looks very alike with both her daughters.
Personality and traits
Misuzu is very strict with kids. Perhaps her bad mother-daughter relationships with her mother had caused her awkwardness with her own daughters. Also, she is incredibly stubborn.