Madonna's young son Rocco followed in his big sister Lourdes' footsteps on Thursday (31May12) by joining his famous mum onstage as a backing dancer at the launch of her new world tour.

The Material Girl kicked off her MDNA trek in Tel Aviv, Israel amid rumours 15 year old Lourdes was planning to perform with her onstage.

But the audience was in for a shock when Madonna brought on her 11-year-old son Rocco, by her moviemaker ex-husband Guy Ritchie, instead.

The youngster wore flowing, priest-style robes to join a backing chorus before changing into a sparkly blue top and headphones to wow the crowds with a dance routine.

Lourdes performed as a dancer at a concert on the singer's Sticky & Sweet tour in 2009.