Actress Kate Winslet was left stunned by grumpy mums she overheard complaining about their sex lives during her research for new movie LITTLE CHILDREN.

The British star plays a desperate young mother in the movie and prepared for the role by hitting playgrounds and parks to eavesdrop on others' conversations.

She says, "Little Children forced me to observe how parents interact with other parents in playgrounds.

"The mothers are doing their knitting on the bench and talking about how little sex they've been having recently, which they do quite publicly, as if they don't think anyone else is listening. But I was."