I think that's the read of the mother, but I honestly really don't see it? Maybe Page 5 could be seen as a bit ambiguous, if you stretch it, but it seemed more like she was reminiscing her girlfriend more than anythingThere's a read where Nagi was attracted to a child, instead of just telling a child they're cute as a compliment. Uh-oh.
And just where was the older sister at the time Meguru was being neglected by their mother? Did Hijiki-sensei forget about her?
Maybe it just reminds her of the ex husband.This is what happens when people with mental health issues have kids before treating them.
Mom has to have some trauma or problems with feeling unloved or abandonement. Why the fuck else would she get jelous of her adorable kid. Any healthy adult would be happy that her child and partner get along.