Melissa Joan Hart
Alberto E. Rodriguez/Getty
11/16/2008 AT 11:30 AM EST
Between potty training her first son and giving birth
to her second, Melissa Joan Hart has had a busy year as a mom.
"It's a constant workout," the ex-Sabrina, the Teenage Witch
star tells PEOPLE of taking care of her sons Mason, 3, and Braydon, 8 months.
That's why she's been able to stay post-pregnancy fit, she says.
"You don't have time to eat because you're chasing them all the time!" she said Friday at the Jonas Brothers launch of 77 Kids by American Eagle in Los Angeles. "You kind of lift them in the car seat, out of the car seat, in the highchair, out of the highchair."
Luckily, she says, her eldest has been making the transition easy with the latest family member.
"He's a great big brother," says Hart "He's just getting to the stage where he kicks [Braydon] when he walks by him. But for the first eight months he's been a dream."
The 32-year-old actress and her husband, Course of Nature band member Mark Wilkinson, welcomed Braydon Hart Wilkinson in March, and so far things are "great" – silly moments and all.
"Because he's teething he sticks his tongue out all the time," she says. "We took family photos yesterday for our Christmas card and he just kept sticking his tongue out. It was really bizarre, but cute."
But it doesn't mean the mom of two doesn't have her own worries about her youngest.
"He's been crawling or scooting for like months now, but he's starting to stand and balance on his own," says Hart. "I'm a little concerned that he's skipping the crawling stage because I hear that they're not good readers if they don't crawl."
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