All better! Sarah Michelle Gellar spent the night of Thursday, January 12, in the emergency room with her 4-year-old son, Rocky Prinze — but her youngest is doing just fine.

“Well I made it 7 years before I had to take one of my children to the ER (I think that’s a pretty good stretch),” she captioned an image of Rocky sitting on a chair at the doctor’s office, via Instagram on Friday, January 13. “It was a long night and apparently a nasty virus, but thankfully Rocky was released. I’m not going to lie, watching your child not be able to breathe, is the most helpless I have ever felt.”

Gellar, 39, then thanked the medical staff for their kind attention and quick work. “Thank you to all the great doctors and nurses (and staff) who work tirelessly 24 hours a day to help,” she continued. “And thank you to his big sister, Charlotte who would not leave his side. (The best moment was when I was filling out his paperwork, and I was asked if Rocky was single - laughter is definitely a great medicine.)"

The Buffy alum shares Rocky and daughter Charlotte, 7, with husband Freddie Prinze Jr. She later shared a cute image of Rocky recuperating in a hospital bed, enthralled by a cartoon playing on the iPhone on his lap.

“Thank goodness for #iphones and #inspectorgadget when your little one is sick in the ER. (He’s better and resting at home now #nastyvirus),” she captioned the image, which she shared with fans via Twitter.

And Gellar knows a thing or two about keeping a positive attitude through tough times. The Cruel Intentions actress has been a pillar of support for her longtime friend Shannen Doherty through the Charmed alum’s battle with cancer.

Last August, Gellar posted an image of the pair together, calling Doherty, 45, her “muse.”

“I’ve always said she is one of the most loyal friends I’ve ever known, and now while she is facing the toughest journey of her life, she is sharing it with friends she has never met in the hopes of helping other people who are going through the same struggle,” Gellar captioned the image. “That’s a true friend #F--kCancer.”

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