It's tough looking after kids, whether you are an average mum or World No 2 Swiss tennis ace Roger Federer's wife. Federer, 36, recently told Swiss TV channel SRF during an interview that his wife Mirka, 40, tends to get so busy with their kids that she is unable to follow his matches, and doesn't even know if he has won or lost.

Mirka, also a tennis player, quit the sport in 2002 after achieving a career-high ranking of No. 76. She married Federer in 2009 and the couple have four kids — two sets of twins — girls Myla and Charlene, nine, and boys Leo and Lenny, four.