The former 'Heroes' star made the announcement on 'The Tonight Show with Jimmy Fallon', where she was promoting her new show 'Legends'. This will be Ali's second child with husband Hayes MacArthur. MacArthur is also an actor who has starred in populart television show 'How I Met Your Mother' and comedy horror sequel A Haunted House 2. The couple met on the set of National Lampoon's Homo Erectus in 2006 and married in 2009. 

Ali Larter
Larter made the announcement on Jimmy Fallon's talk show

Larter last appeared on Jimmy Fallon's talk show in 2010, where she announced she was expecting a baby boy. Theodore Hayes MacArthur was born in December the same year. Larter referenced this in her chat with Fallon this time around, saying "Yeah, I came on and... I was pregnant. It went so well that I said to my husband, 'I'm going on 'Fallon.' You know what that means. Gotta get pregnant". 

She also revealed she had been trying to keep the pregnancy underwraps. "I've been trying to hide it as much you can, and when you're in the public eye, it's really scary in the beginning and so, I was still shooting my spy drama -- I'm doing 'Legends' with Howard Gordon. ... I have to be like a covert spy in my real life too, so like I'm wearing blazers and pushup bras and everything you can do to distract as the bump is like growing." 

'Legends' is Larter's latest television project and stars British actor Sean Bean in the lead role. It is based on the book 'Legends: A Novel of Dissimulation' by Robert Litell and focuses on an FBI agent who transforms himself into a different person with every case he takes on.  

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