Men who grow up with sisters are rubbish at housework, according to new research.
Apparently they are less likely to get involved with the cooking and cleaning and more likely to fulfill 'traditional' gender roles.
And – don't shoot the messenger, please – the researchers say the women of the house are to blame.
The research, published by academics at Stanford Business School and Loyola Marymount University in the US found that men who had sisters were 6.6 per cent less likely to do the dishes at home because when they were growing up young daughters were more likely to be asked to help in the house.
This creates an expectation in boys that women will pick up after them that stays with them into adulthood.
The paper, published in the Journal of Politics, used data from a large study which tracked the views and habits of thousands of American families over three decades from 1965 until 1997.
The authors wrote: "Younger sisters have been found to make male siblings less likely to be assigned to female-stereotyped tasks. This effect emerged in a striking way for boys.
"In summary, we find that having sisters makes males more politically conservative in terms of gender role attitudes and partisanship.
"Particularly for gender role attitudes, we find that these effects persist into adulthood."
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