Maomao interprets Fengxian singing children's songs as her regressing to her own childhood.
But she still plays Go and treats Meimei the same, so it's more likely she is aware she is older.
But why else would she be singing children's songs and lullabies? Well, this is a woman, who against all rules did everything to become pregnant. I am convinced Fengxian wanted to be a mother, and would have been a great one if not for the loss of hope, probably ppd and then illness breaking her mind. I am convinced in her mind she's singing those songs for her little baby.








