People.com Celebrity Parents Guess the Celebrity Baby 18 -- pregnancy edition By Staff Author Published on January 9, 2008 05:35 PM Share Tweet Pin Email We previously found out that readers loved the Guess the Celebrity Baby feature, so we’re bringing it back. To start off with here is a celebrity mom and child star. She is pregnant with her second child (whose sex she knows, but is keeping a secret — for now) and already has one son who will celebrate his birthday on Friday. The new baby is due in March and she currently writes a pregnancy column for us. Have you guessed who it is already? Continue reading to find out who this celebrity mom is. If you have any suggestions of pregnant celebrity moms or celebrity babies you would like to see featured please email them to shannon@celebrity-babies.com Photos by Flynet. It’s Melissa Joan Hart, 31. Melissa is married to musician Mark Wilkerson and already has one son Mason Walter, who will celebrate his second birthday this coming Friday. Their next baby is due the first week on March and they do know the sex but are not sharing. Missed some of Melissa’s columns? Get up to speed so that you are ready when we post the next column sometime next week.