Olivia Wilde and Jason Sudeikis expecting second child

Olivia Wilde and Jason Sudeikis are expecting their second child together.

The Hollywood couple's baby son Otis will celebrate his second birthday on Wednesday (20Apr16), and his mom has presented him with an early surprise present - the news he is set to become a big brother.

Taking to her Instagram page on Monday (18Apr16), Olivia, 32, confirmed the happy news by posting a black and white photo of herself sitting beside Otis, with their stomachs on display.

"Matching baby bumps" she wrote alongside the shot, in which she beamed down at her little boy as she sat cross legged on a bed wearing black underwear and an open white shirt, with a visible bump already on display.

Meanwhile, little Otis grins up at his mother as he sits cross legged beside her with his white T-shirt rolled up.

Olivia recently told People magazine that she and Jason, 40, were ready for another baby.

"I’m desperate for more (kids)!” she said. “I love my siblings so much and Jason has incredible siblings too. The more the merrier.”

She also confessed to E! News she was feeling jealous and maternal towards her actress friend Rose Byrne, who is a new mom with her son Rocco.

Asked if she is experiencing baby fever, the beauty exclaimed, "Yeah! Everything makes me want another one!"

Olivia and Jason first got together in November 2011, before becoming engaged in January 2013.

The Vinyl star was previously married to Italian filmmaker Tao Ruspoli for seven years until March 2011, while Jason tied the knot with 30 Rock actress Kay Cannon in 2004 after five years of dating. They divorced in 2010.