This update is all smiles. 

Mandy Moore shared how her 2-year-old son Gus is doing following his recent diagnosis with Gianotti-Crosti Syndrome—a type of childhood skin rash that can cause blisters on the legs, butt and arms. And though the condition can last as long as 6-8 weeks, the This Is Us alum is happy to report the 2-year-old is feeling good. 

"Someone may have a crazy rash," she captioned a July 31 Instagram Story featuring Gus smiling with a breakfast bowl in front of him, "but he's still a champ!!"

And of the breakfast all over his face in the photo, the "Candy" singer added alongside the laughing-crying emoji, "He loves his oatmeal."

Mandy first revealed that her and husband Taylor Goldsmith's oldest son had developed a skin condition in a lengthy post on her Instagram Stories detailing the steps it took to diagnose the rash. 

"This sweet boy woke up with a crazy rash on Saturday am," the 39-year-old wrote in her July 28 note alongside a picture of Gus. "We tried to deduce what it could be and did anything to help him find relief from the itch." And it took a trip to a pediatrician, dermatologist and pediatric dermatologist before they were able to diagnose the rash as Gianotti-Crosti Syndrome.

But it would appear that Gus is always going with the flow—in addition to being a good sport, she shared at the time that amid the many doctor appointments, the little boy was all "smiles and laughs like the rockstar he is."

Earlier this year, the Walk to Remember star, who also shares 9-month-old son Ozzie with the Dawes frontman, reflected on life with two little boys. And she even revealed whether she is looking to grow her family of four. 

"Truth be told, I haven't shut the door on a larger family," she told E! News on a March 23 episode. "I don't know what my husband is thinking. I know right now, he's sort of like, 'Whaaat? That's crazy! It's so hard.' And it is. It's so hard. It's non-stop, all hands on deck right now. So maybe, perhaps. but I don't know."

But one bit of calm amid the chaos? The bond between the two brothers.

"Gus is like a superb big brother. He relishes that role. He's not super jealous," Mandy added. "Once Ozzie got here, he was just super protective of him. He understands how fragile Ozzie is. He wants to cuddle him. It's very sweet."

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