Mothers are more critical of their daughters than their sons and let boys get away with more, a poll suggests.
The survey by the website Netmums found mothers were twice as likely to be critical of their daughters than their sons (21% compared to 11.5%).
Of the 2,672 mothers questioned, 15% said they had formed a stronger bond with their sons than their daughters.
The findings also suggest 51% thought it was wrong to treat boys and girls differently.
More than one in five of the mums (22%) surveyed agreed with the statement that they let their sons get away with more, turning a blind eye to behaviour for which they would reprimand their girls.
The poll found mothers were more likely to attribute positive personality traits to their sons than their daughters.
Boys were more likely to be described as funny, cheeky, playful and loving, while girls were more likely to be described as stroppy, eager to please, serious and argumentative.
Almost half of mothers questioned (48%) said their sons were mummy's boys.
Crissy Duff, psychotherapeutic counsellor with Netmums, said: "Women in particular seem to carry the feelings of parental disapproval and negative typing into their adulthood.
"This could be why women are far more self-critical than men, who have a more happy-go-lucky attitude when it comes to making mistakes and moving past them."
Siobhan Freegard, co-founder of Netmums, said: "As a mum of two boys and a girl, I know first-hand that, try as we might, it can be very hard to treat all of your children the same.
"This is a great wake-up call to mums to help break these gender cycles and even out the differences in how the sexes behave and think about themselves.
"It's a powerful call to change the current gender dynamics, which is a huge ask, but an achievable one."