News Limited reports Sebastian's wife Jules Egan gave birth to a baby boy late on Saturday, weighing in at 2.7kg.
Hudson James Sebastian is the couple's first child and has already made his debut on social networking site Twitter after his dad released two images of his son on Sunday.
"I'm in love.He's a little dude," Sebastian tweeted.
The Daily Telegraph reports the couple has secured a magazine deal with New Idea believed to be worth $200,000.
