How was it used? Context is very helpful. Darling probably does mean that it's about a girl. It means that that person is very attached to her mother. For a girl, this isn't as bad--or as intended to be offensive. Calling someone a "mamma's boy" (mother's boy-less common but means the same) is generally intended to be offensive if spoken by someone the recipient doesn't know well. Sometimes guys will joke with one another and call each other "mama's boy" but this is the only context where it is not as offensive. Hope that helps. :)

I would say it refers to a spoilt child and it could be either a boy or girl.

mother's prized possession , e.g. her child -- I get the feeling it is leaning more towards daughter

То же, что и "mother's boy" - "маменькин сынок".

Thanks everybody!!!