The Good Will Hunting star gave birth to little Henry Story Driver in 2008 and she refused to come clean about the identity of the baby's dad.
Driver finally revealed last month (Feb12) that Henry's father is a TV writer, who is gradually stepping up his responsibilities as a new parent, and the 42-year-old actress admits she had a laugh about all the speculation.
She tells U.K. talk show host Alan Titchmarsh, "It wasn't really anyone's business in the first place. Everybody has their personal life and their story behind certain things and those were my choices.
"Rather a lot was made of it, which I was quite surprised by - I think everyone thought it would be someone fantastically famous, who the dad was. It was a bit of an anti-climax... I did disappoint people by it just being a normal bloke.
"Frankly I don't think people are that interested because he's not Colin Farrell, who I think a lot of people thought the dad was for a while, which was very funny to me."