Brian Austin Green credits Reese Witherspoon with helping to keep the recent birth of his son a secret.

The 'Wedding Band' actor and wife Megan Fox welcomed Noah Shannon into the world on September 27 but managed to keep the news quiet for almost a month as most of the attention went to Reese Witherspoon who had her son Tennessee at the same time.

Speaking on 'On Air With Ryan Seacrest', he said: ''We got really lucky. And I've been wanting to send Reese Witherspoon flowers for, like, a month and a half. 'Cause she actually gave birth, I think the day before us in Santa Monica. We were lucky enough to go in at 2:30 in the morning to the hospital and nobody knew. We were there for two days . . . and we heard Reese was at her place and had a baby, and we got out of the hospital and nobody knew.

''We got home and thought, 'This is unbelievable. Because we weren't expecting to get away with it. So we just figured we would go with it as long as we could.''

Brian, 39 already has a son Kassius, 10, from a previous relationship and his 26-year-old wife has previously said how being a stepmother makes her extremely happy.

She said: ''A lot of things make me happy. But I feel unbelievably happy when my stepson tells me I'm beautiful. When I started living with Brian, his son was only two and I was 18. I've been looking after Kassius since he was three - it's part of my world that very few people really ever understood about me.

''I love being a stepmom and the experience grounds me when nothing makes sense in my life.''