True grit: Missing 120 days of school to becoming co-valedictorian

Sarah Penney, 19, a senior at Maine Virtual Academy, is about to graduate in June. The South Thomaston teenager wasn't sure she'd ever get to this day. "It sounds like a cliché but it feels like a dream come true," she said.

Up until the past two years, Penney has suffered from flu-like symptoms, and the very occasional headache, which caused her to miss a tremendous amount of school.

"I had vertigo and light sensitivity," she said. "I was constantly nauseous and couldn't keep anything down. It generally just made me feel like I had severe stomach flu symptoms mixed with the after effects of a particularly nightmarish teacup ride."

For 10 years, doctors misdiagnosed her symptoms as a sinus infection combined with allergies, due to how her symptoms appeared seasonal. All of the medications and antibiotics she was prescribed only made the symptoms worse.

Penney said she didn't get an accurate diagnosis until her sophomore year in high school, 2014.

Read more of her story here.