By Sarah Bull

PUBLISHED: 09:11 GMT, 27 March 2012 | UPDATED: 10:55 GMT, 27 March 2012

She welcomed her first child into the world when she gave birth to son Milo in August last year.

And now Alyssa Milano is getting used to being a working mother, after being cast in new primetime show Mistresses.

The 39-year-old actress was snapped on the set of the upcoming ABC show toting her gorgeous little boy.

However, Alyssa later took to her Twitter page to admit that it is going to take some time for her to get used to balancing her work life and her family life.

She tweeted: 'Letting Milo take a nap in my arms before I have to go to work on Mistresses. This working mom thing is no joke. You all made it look easy.'

Alyssa, who is married to CAA agent David Bugliari, later responded to a question from a follower on the micro-blogging site about how she has managed to find a routine with her seven-month-old son.

She replied: 'Our schedule is never the same so I'm not sure a routine can be found. Milo came to visit today though and it made me so so happy.'

It was revealed earlier this week that former Charmed actress Alyssa had been cast in the new series Mistresses, which will fill the slot soon to be vacated by Desperate Housewives.

The programme, adapted from the British series of the same name, tells the story of four women with very troubled love lives.

Alyssa will star as Sarah in the show, a married lawyer who finds herself spending most of her time with her handsome law partner rather than her husband.

The series will also star Jes Macallan as Josslyn, Rochelle Aytes as April and former Lost actress Yunjin Kim as Katie.

Alyssa, who was recently seen in romantic comedy New Year's Eve, is most famous for her roles as Phoebe Halliwell in Charmed and Jennifer Mancini in Melrose Place.