Life was unstable as they struggled to make ends meet, and only got more so as he was shuttled between family members and shelters before he and his siblings were placed in foster care.
When I stopped by Mastery Charter's Thomas Campus high school in South Philly before his June 20 graduation, Cornish didn't recall many of the details of those early days.
"I just remember the struggle, never staying put, never having friends," he said. "I remember feeling like everything was just happening and there was nothing I could do to stop it."
What remains a vivid memory is that even as a little boy, school was his sanctuary - the constant in a life full of uncertainty.
"It was always my safe haven, even when things were going good with my family," he said.
At Mastery, Cornish started to think about college. He just wasn't sure which one, until he visited Xavier University in Cincinnati.
"I felt like it was a preview of what my life could be if I went there," he said, a dreamy look in his eyes. "I could see my future there."
Cornish was thrilled when he was accepted - and then he saw the price tag: about $40,000 a year. Even with financial aid and scholarships, he was short $17,000 for his first year.
"I panicked a little bit, but after that, it was determination fueled by panic," he said.
Cornish knew it was popular for people to turn to online campaigns to fund projects and big ideas. Maybe, he hoped, people would want to invest in a kid who wanted to pursue his education more than anything else, who dreamed of studying international business and traveling and making something of himself.
He got on Indiegogo, a crowd-funding site where, unlike Kickstarter, fundees receive donations even if they don't meet their goal amount. He posted "A Dollar and A Dream" campaign, where in a video and short summary he asked 17,000 people to donate $1.
In return, he vowed to get his college degree and help other foster-care children pursue their educations. He wants to form "A Dollar and A Dream" foundation.
"I didn't want any pity. I just wanted people to know my story and to know what I was looking to gain," he said.
His mentor, Mastery's former dean of students, Tony Anderson, was supportive, but concerned about a potentially negative response.
"It was about the $300 mark where I realized it was working, and I nearly broke down in tears," Anderson said. "I'm just so excited for the potential of him."
Cornish's goal was $17,000 in 60 days. About 500 people, mostly Xavier alumni, pledged $11,224. He received additional scholarships that filled the gap for his first year, including $5,000 from the Foster Care to Success program.
But one contribution was especially meaningful. Cornish recently found out that his paternal grandmother had put aside a little money for him. "Makes me feel bad for what I sometimes put her through," he said.
He shouldn't feel too bad. His grandmother is clearly proud. "He did this all on his own," Muhammad said. "That child made sure he got up every day and got himself to school, no matter what. It gives me goose bumps just thinking about it."
And what about year two, three and four, where Cornish will have to come up with a $17,000 shortage each year? "I have to believe that if I get there, I can find a way to stay there," he said.
Days before his graduation, Cornish was already feeling the emotion of the day to come. His mother and grandmothers would be at the graduation. So would his father, with whom he reunited and is living with until he heads to Xavier in August. He also invited his last foster mother.
"I didn't think I could make it this far," he said. "Statistically, a black male going through all of that is not supposed to make it. It's kind of overwhelming and unexpected."
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