"If I hadn't chalked it all up to stress and fatigue, I would've caught this sooner," the actress said of the autoimmune condition, which causes the overproduction of thyroid hormone.

Erin Moriarty has been diagnosed with Graves' disease, the actress announced on Instagram Friday. Moriarty shared a text message in which she detailed her symptoms and a series of selfies along with a caption in which she encouraged her followers to "go get checked" if they experience similar symptoms.