The House of Lies actress previously admitted that she was keeping the sex of her child secret from the public until she gives birth this spring.
Bell was speaking on The Ellen DeGeneres Show about how her husband Shepherd will have a "tiny partner" for his off-roading hobby, when the chatshow asked her directly if she is having a son.
"Maybe," Bell replied to Ellen DeGeneres's question.
The star quickly added: "Do you have to be a boy to off-road? Absolutely not! I think he's going to force [the baby], even if it's a sloth, to off-road."
Bell also revealed that she has come to love being pregnant because her "self-esteem has never been higher".
"I look in the mirror and I think it's the reverse body dysmorphia because I can understand what my shape is, but I see Brooke Shields [who had postpartum depression]," she said.
"And it doesn't make a lick of sense, but it's something that the baby's giving me hormonally makes me feel really giggly and happy."
Bell recently joked that pregnancy has left her feeling "happy" and "dumb", which she described as quite a change from her normal personality.
Her series House of Lies airs Sundays at 10/9c on Showtime.
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