in "Small", she called her son to tell him that his father was coming to visit him. Shin mentions that his visit was her idea, because she thinks they need to spend more time together. Later in the episode, when Shin observed Mao Mao's fighting prowess, Mao Mao's mother can be partially seen in a flashback, wherein she is shown cradling her newborn son in her arms.
It only shows her arms and chest in a flashback of Shin Mao in "Small", holding Mao Mao after he was born, but we can see she has a bulky body.
In contrast to her husband, Mao Mao's mother seems to pay more attention to her son, being the first person to cradle him after his birth and their relationship is apparently better because Mao Mao never mentions any issues related to her.
- During the flashback in "Small", she can be seen wearing a hospital gown and an ID bracelet, which suggests that she gave birth to her son in a hospital.