Busy Philipps has baby names on the brain! The pregnant Cougar Town actress revealed her second baby-to-be's gender to Us Weekly -- it's another girl! -- and now she's debating potential baby names on Twitter.

"The guys at the post office just suggested I name my baby Rihanna or Aaliyah," Philipps, 33, who is already mom to 4-year-old daughter Birdie, tweeted Thursday, Apr. 25. "So apparently, I'm giving birth to an R&B superstar."

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On second thought, maybe naming her second daughter after Rihanna's nickname wouldn't be such a bad idea. She later asked her Twitter followers, "Is it weird that now I think RiRi Silverstein is kind of cute?"

When one follower suggested "Ciara" instead, the actress joked, "I worry she would lack mainstream appeal."

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Or perhaps Philipps should tribute to TV mogul Oprah Winfrey instead. "Not a joke, in a hormone-induced haze, I actually DID try to sell my husband [Marc Silverstein] on naming the baby Oprah," she tweeted. "Because I love her so much."

The former Dawson's Creek star told Us that her family is "really excited" to welcome another girl, but she is a little worried about how Birdie will adjust. "I'm planning for that moment when she asks, 'When does she go back?'" she joked.

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Birdie has her own name suggestion for her littler sister, but Philipps isn't sold on it because it reminds her of a TV character. "My daughter wants us to name the baby Maeby!" she shared with a follower. "I obviously just think of arrested development!" (Alia Shawkat played Maeby Funke on Arrested Development.)

Tell Us: What do you think Philipps should name her second daughter?

This article originally appeared on Usmagazine.com: Busy Philipps Jokes About Potential Baby Names: Oprah, Rihanna, Aaliyah or RiRi?