Mandy Moore Shares Son Gus Is Battling Flu, Croup as She Tries to Keep Baby Healthy: 'Exhausted'

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Mandy Moore is trying to keep her newborn baby healthy with a sick toddler in the house.

Sharing a selfie while holding son Ozzie, 9 weeks, on her Instagram Story Thursday, the This Is Us star, 38, revealed that she's juggling keeping her newborn healthy while son Gus, 22 months, is sick.

She captioned the shot in checklist form, listing that she has a "toddler with the flu and croup," an "exhausted household," and is "trying to keep myself and the newborn healthy and nursing around the clock."

The Mayo Clinic describes croup as "an infection of the upper airway, which obstructs breathing and causes a characteristic barking cough," and notes that the infection generally occurs in children.

Despite the tired mom's tough time, she managed to exercise while her kids slept, as she shared in a later post.

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Mandy Moore/Instagram

RELATED: Mandy Moore Shares Adorable Photo of Son Gus Cuddling Brother Ozzie: 'Only Holiday Gifts I Need'

In the sweet photos shared by the actress earlier this week, Moore cradled Ozzie while husband Taylor Goldsmith held Gus, and the family of four smiled in front of their Christmas tree together. A second photo showed Gus adorably leaning over to give his baby brother a kiss on the head.

"From our family to yours, Merry Christmas and Happy Holidays!!" wrote Moore on Instagram.

In photos on her Instagram Stories, Moore sat with Ozzie while Gus opened his presents and Goldsmith looked on. "Anything 'Toy Story' themed or anything with wheels was the biggest hit for Goose."

"This guy still smells amazing after 4,000 spit-ups," the actress added on a sweet photo of Ozzie in a baby bouncer.

Moore and Goldsmith, 37, welcomed their second baby together in late October.

"Ozzie is here!" Moore wrote the sweet birth announcement at the time, which featured a carousel of black-and-white photos from the hospital.

"Oscar Bennett Goldsmith arrived a little late but with much aplomb (and an easier/speedier delivery than his big brother, much to the delight of his parents)," she continued in the caption. "Every adage is true: our hearts have doubled in size and the immediacy of the love is astounding. He is beyond words and we are so grateful for our family of four! 💓💓💓💓."