Sienna Miller is a mum Sienna Miller Mon-09-Jul-12 09:43 Share this By Jay-Jay FeeneyJude Law’s ex SIENNA MILLER has given birth to her first child with her actor boyfriend Tom Sturridge.No word on what the sex or name is. You May Also Like What sex is Mila and Ashton's baby?! Celebrity Baby News! Is Rihanna pregnant? Become a fan of The Edge on Facebook and on Twitter .