Jennifer Hudson says giving birth to her son motivated her to slim

The Oscar winning actress and singer lost 80lbs using Weight Watchers after having David Otunga Jnr in August 2009.

She told CBS's Early Show: 'Towards the end of my pregnancy I was just like 'I want my body back to whatever it was before'.

'Then I realised I had the power to get myself back and wanted to do something different with it.

'My son is my motivation and inspiration for everything. I realise that he's watching, he's like a sponge right now absorbing everything we do.

'He's always slept through the night so we lucked out big time!'

The 29-year-old stunner, who is married to reality TV star David Otunga, told how she has recently moved her family back to her hometown Chicago - the city where her mother Darnell Donnerson, brother Jason and nephew Julian, 7, were fatally gunned down in October 2008.

William Balfour, the estranged husband of Hudson's sister Julia, is awaiting trial for the triple murder.

Jennifer says she has decided to raise her own toddler son in the Windy City despite it holding such painful memories.

'We just moved back home and it's amazing,' said the Spotlight singer.

'I didn't expect to come back to Chicago so soon but just bringing my baby home, we wanted to be near family and for him to grow up near family.'