The She's All That star showed off her baby bump in a pretty satin dress at the Entertainment Weekly party at the San Diego convention on Saturday night (20 July).
Rachael and her Vampire Diaries star husband Daniel Gillies announced back in May that they are expecting their first child together.
Recently, the actress joked that she was more concerned about what happens after the birth than the birth itself.
"I'm less nervous about the getting it here, than I am about the keeping it alive part," she told Access Hollywood Live.
Rachael, 33, married Daniel in 2004, but waited nine years until trying for a child.
"We're both people who like kids, but we weren't jumping up and down, like, 'Oh my God, let's start that chapter of our lives,'" she told People. "Now that we know what our lives are going to look like — sort of — for the next couple of months, we just felt like it was the right time finally."
She added: "We're not getting any younger."
Rachael currently stars on the crime drama Perception. Reveal caught up with her back in October to chat about the show - you can read that interview here.
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