Actress Mandy Moore recently shared that her two-year-old son Gus has Gianotti-Crosti Syndrome, a rare skin condition that causes an itchy and blistering rash in children, according to WebMD.

In posts on her Instagram Story, Moore shared how Gus, whom she shares with her husband Taylor Goldsmith, woke up with a mysterious rash, which was initially challenging to diagnose despite several doctor visits. The “This Is Us” star wrote, “This sweet boy woke up with a crazy rash on Saturday am. We thought maybe an eczema flare? Poison oak? Allergy. We tried to deduce what it could be and did anything to help him find relief from the itch.”

Moore continued, “Went to urgent care. Pediatrician. Dermatologist. Pediatric dermatologist. All the while, he smiles and carries on like the rockstar he is.” In another post, she explained that doctors finally identified Gus’ skin condition as Gianott-Crosti syndrome.  Moore wrote on an image of Gus in which the child’s legs were seen covered with red patches of skin, “Turns out it’s a viral childhood rash that just spontaneously appears called Gianotti-Crosti syndrome.”

She continued, “It’s all over his legs and feet (ouch) and the backs of his arms but nowhere else. There’s nothing to do but a steroid cream and Benadryl at night. And it could last 6-8 weeks. Ooooof. Anyone ever experience this?” Moore concluded by sharing another photo of Gus and opened up about parenting challenges. She shared, “All of that to say, this parenting thing is weird and hard, and sometimes you feel so helpless (and yes, I’m ever so grateful it’s only an itchy skin condition.) Kids are resilient, and as long as he’s smiling through it, we are a-okay.”

Per the National Organization for Rare Diseases, Gianotti-Crosti syndrome is a “rare skin disease affecting children between nine months and nine years. Significant symptoms may include blisters on the skin of the legs, buttocks and arms.” NORD also noted that an underlying viral infection typically precedes the disorder.

In addition to Gus, Moore and Goldsmith, who tied the knot in 2018, are also parents to nine-month-old Oscar “Ozzie” Bennett. Recently, the “A Walk to Remember” actress reflected on the “chaos” that she and the Dawes frontman experience daily as the parents of two toddlers.

Moore captioned a photo of Ozzie and Gus, “These dudes rule my heart. Each night, Taylor and I fall into bed after we’ve put them down, after we’ve straightened up from the chaos of dinner/bath and set up for the next morning, and we chat about the day and just how utterly nonstop and gratifying it is.”

She continued, “You never know what the day will bring, and you roll with it to the best of your ability, right?” Moore concluded, “All of that to say, I wouldn’t have it any other way. I mean, I do look forward to feeling moderately well-rested sometime in the next decade? But [shrug emoji.]”