um, I think it works this way...
the mother once was a little girl, yeah?
so she'll tend to compare her daughter with herself [sub-consciously], and will perhaps expect the daughter to live up to certain expectations or fulfill certain dreams that she had when she was a little girl.
also, the mother, having once been a young girl, also believes that she has experienced more than her daughter, and thus tries to implement more rules to prevent her daughter from making the same mistakes that she has made.
[you can also replace the words 'mother' with father and 'daughter' with son, but if you change one you must change the other xD]
but then, the mother was never a little guy

.
she does not expect guys to behave in a certain way or develop at a certain stage [because she herself was never a guy].
when the little boy makes a mistake, she'll simply think, "oh, guys are like that." as opposed to "when I was little, I didnt do that."
so there's less stress in the relationship xD.
and come on, all females dote on little boys

.