New mum Olivia, carried her precious cargo through the streets of New York, exactly a week after giving birth.
The Hollywood actress, 30, proudly took to Twitter on 23 April to announce the birth of her first son in an amusing post.
"Ladies and gentlemen, Otis Alexander Sudeikis has LEFT the building! (I'm the building)," she tweeted, alongside a black and white photo of mother and baby.
In the sweet snapshot, Olivia is pictured cradling her newborn son close and smiling with her eyes closed. The bundle of joy is wrapped up in a blanket and nestled into his mother’s chest, with his face hidden from view.
The image caused a stir on Twitter and was retweeted more than 4,000 times in less than four hours.
This is the first child for Olivia and Jason, who announced that they were expecting a child last October.
The Rush actress confirmed early on that she was having a boy, and hinted at the 2014 Golden Globes that her due date was on 4 May, as she told Ryan Seacrest, "May the fourth be with you!" when probed.
Olivia Wilde and Jason Sudeikis
Just hours after their sunny stroll with Otis, Olivia and Jason made their first post-baby red carpet appearance to attend the 2014 Ms. Foundation Women Of Vision Gala.
The 30-year-old actress looked great in skinny black jeans, a white T-shirt and a stylish blazer. Meanwhile, Jason looked dapper in a grey suit.
Olivia and Jason, who have been dating since November 2011, got engaged in January 2013.