'Harry Potter' 's Jessie Cave Hospitalized After Contracting COVID During Pregnancy

Jessie Cave is battling COVID-19 in her third trimester.

The Harry Potter actress — who is currently expecting her fourth child with comedian Alfie Brown — revealed over the weekend that she was in the hospital after contracting the virus.

"Triage, once again ... " Cave, 34, captioned a Saturday photo of her legs as she sat propped up on a hospital bed, a monitor strapped to her bare belly.

"Anyone else had covid in 3rd trimester & had it hit them like a tonne [sic] of bricks for weeks?
🤯🤯🤯🤯🤯🤯🤯🤯🤯🤯🤯🤯," she added.

Cave's Harry Potter costar Devon Murray commented, "Jessie, I'm so sorry you're going through this now 😭 hoping for a speedy recovery ❤️."

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Cave, who's best known for her role as Lavender Brown in the Harry Potter series, announced on Instagram in December that she's expecting her fourth baby with Brown. (The two also share sons Abraham, 16 months, and Donnie, 7, plus daughter Margot, 5.)

Cave shared the exciting news with a series of mirror selfies taken by her sister Bebe that revealed the actress's baby bump.

"💘🤰can't hide this new baby anymore💘🤰," she captioned the post.

Her partner Brown also announced the news on his Instagram page alongside a sonogram photo.

RELATED VIDEO: Harry Potter Actress Jessie Cave's 11-Week-Old Son Is Hospitalized with COVID-19

Cave's COVID-19 diagnosis comes just over a year after her son Abraham was also hospitalized with the virus, at 11 weeks old.

After Abraham was home, the actress reflected on the experience on the U.K. talk show Lorraine, saying, "Nothing has gone to plan, which I guess everyone can relate to this year. It was a really scary start."

"He was in the neonatal unit after a really sudden, quick labor. He came out within 45 minutes, so he was just a bit like, 'What's going on?' and was taken to the neonatal unit. He's 11 weeks now, and it's just been, I couldn't believe it when we found out. But I almost can believe it because it's been such a strange period of time for everyone. Very scary."

Cave said she wasn't aware how her son caught the virus and that she herself was "symptomless." Sharing a clip from the TV appearance on Instagram, she advised parents to "basically trust your mother's instinct ... and go in to hospital if you are at all concerned."