Kathryn Tucker, a senior care coordinator for an Arizona insurance company, had just gone to bed when she felt a sharp pain the back of her head on the right side before her vision went out and she went numb.
Her brother was at her Chandler, Ariz., apartment and got her to the hospital where doctors at first dismissed her symptoms as a migraine with aura. But Tucker, only 26, was having a stroke.
"I was absolutely terrified," said Tucker, who was sent home from the emergency room that day in July 2012 without medical intervention.
"I slept for three days straight," she said. "Then, when I woke up, my vision was horrible. Everything was distorted and one-dimensional. I could barely get around."
Her health deteriorated so she ended up going to an urgent care facility. From there, she was referred to a neurologist who diagnosed a stroke.
Nine months later to the day, her twin sister, Kimberly Tucker, suffered a stroke in exactly the same way, except on the left side. Kimberly Tucker had left school in Tucson to take care of her sister after her stroke. Then in April, their roles reversed.
The Tucker girls are fraternal twins and do not share the same DNA. There is a family history of stroke, but doctors are unsure of a genetic link until further testing is done.
Both suffered a stroke on opposite sides of the occipital lobe, which sends visual input from the brain to the retinas.
"Honestly, it's rare for us to actually evaluate two sisters who've had strokes within months of each other," said Dr. Joni Clark, a vascular neurologist at Barrow Neurological Institute in Phoenix. "If they had a family history, it would not be a surprise. It's quite uncommon."
Stroke is a leading cause of death in the United States, killing nearly 130,000 Americans each year, according to the Centers for Disease Control and Prevention, which observes National Stroke Month in May.
About one-third of strokes are believed to occur in people younger than 65.
For those younger than 45, the stroke risk has jumped 14 to 20 percent, according to Clark.
"We see this mainly among young people who have risk factors that you should see in elderly patients.
"Here at Barrow, we see a huge population of stroke patients -- and, in my own experience, which is anecdotal, I see a fair number of young people with stroke," said Clark. "The majority are spontaneous."
Obesity, which leads to diabetes, high blood pressure and high cholesterol, is a risk.
"You'd also be surprised how many young adults don't exercise," said Clark. "It's sad, because the rise is due to good, old stroke risk factors that shouldn't happen when they are young."
Doctors say that lifestyle habits are linked to an increase in the incidence of strokes among young people. Kathryn Tucker was a smoker and had stopped using birth control just weeks before her stroke. She also was a migraine sufferer.
It was discovered later that Kathryn Tucker had a PFO, or patent foramen ovale, a small hole in the heart that may have contributed to her stroke.
"There were several things that probably all together put Kathryn at risk," said Clark, who treated Kathryn Tucker, but not her sister.
Kathryn Tucker said her prognosis is "really good" now that she has stopped smoking and taking the pill.
The twins said they were also worried about their overuse of caffeinated energy drinks -- three to four a week, although there is no medical evidence linking those drinks to stroke.
"Don't think you are impervious to stroke," said Kimberly Tucker, who is still undergoing therapy. "We think we are invincible until we are not. This taught us a huge lesson that we are not guaranteed great health and we need to take care of our bodies."
Kimberly Tucker, unlike her sister, did not have a PFO and was an avid runner.
"On the day of my stroke I did a 5K run," she said. "I was feeling extra thirsty the whole time and went home to take a nap."
When she woke up, Kimberly Tucker felt a sharp pain on the left side of the back of her head.
"My vision closed in almost completely," she said. "I wasn't making a lot of sense and was not able to form complete thoughts. But I knew I was having a stroke."
Remembering what her twin sister had gone though, she immediately called 911, then her sister, who told her to take her blood thinners, a move that might have saved her life.
"I instantly knew I had a stroke because I was suffering from many of the same symptoms as my sister," says Kimberly Tucker. "The EMT's told me that the chance of both me and my sister having a stroke this young was that of being struck by lightning twice. They thought I was suffering from dehydration or heat stroke."
Later, doctors discovered Kimberly Tucker had arrhythmia, which may have been a contributing factor to her stroke.
Today, both girls are doing well after occupational and speech therapy, though they still have some visual deficits and are not allowed to drive.
"I still notice some weakness when I am tired," Kathryn Tucker said. "Otherwise, I am fine, physically back to normal."
"We are super close," said Kimberly Tucker of her twin. "I think we always have been close, but this definitely brought us closer. Honestly, she is the only person who understands because we are going through it together."