British actress Emily Mortimer is disturbed by her son's liberal use of foul language - because he's only two years old.

The LOVELY AND AMAZING star's tot SAM, who celebrated his second birthday on 26 September (05), has stunned his mother with his colourful vocabulary - and she insists she has nothing to do with it.

She says, "He's got the foulest mouth - and I don't know where he gets it from.

"Yesterday, I went to put a video in the machine, and he said, 'Oh, not f**king Elmo again!'"