Miles Austrevich, who planned to enroll in Yale’s class of 2017 and was known for his fierce optimism and easygoing sense of humor, died on Dec. 23 at his home in Chicago after a four-year battle with brain cancer. He was 20.

Austrevich was diagnosed with cancer when doctors discovered he had a brain tumor in 2008. He graduated from Northside College Preparatory High School in Chicago in 2011 but deferred his enrollment to Yale twice, when his cancer recurred that spring and again in December 2011. His parents, Len Austrevich and Adriene Booth, said he hoped to soak up as much knowledge as possible at Yale, on subjects including literature, physics and endocrinology.

“Part of his whole energy and aura was looking at the glass as all-full, not even half-full. He was such a sweet soul,” his father said. “It was so, so infectious.”

Austrevich had a wide range of interests, from electronics and Apple products — “he was totally a technology geek,” his father said — to literature, film and photography. Mary Mussman ’15, Miles’ friend from high school, said he was “notorious” for his good taste in music and would fill friends’ iPods with his collection, which was too large to fit on his computer. She remembered how they would listen to artists like Yelle and Flight of the Conchords together during French class, and Booth, his mother, said Austrevich’s tastes spanned genres, including alternative acts like Beach House and electronic bands like Hot Chip.

Mussman said Austrevich “almost oozed cool,” adding that he had a strong creative streak, cool clothing and the “chutzpah” to follow through with ideas like tattooing the words “No Chloraprep,” an antiseptic commonly used in hospitals to which Austrevich was allergic, onto his arms.

Austrevich’s friends and family members noted his keen sense of humor and his ability to adapt his jokes to different contexts, switching between satire, puns or silly jokes with ease.

Len, Austrevich’s father, is a professional comedian, and he and his son’s shared affinity for humor prompted Len to start, a website where people could submit videos of themselves telling jokes to Austrevich as an effort to cheer him up during treatment. The site has received 3,100 jokes, from friends, strangers and celebrities like Jay Leno and Amy Poehler.

Len said his son loved the site, recalling a “particularly grueling” day of chemotherapy Austrevich had last January that left him too drained of energy to walk from his kitchen table to the hallway. During the bout of exhaustion, Len received a video of a child rapping, which “completely energized” Austrevich to the point where he could get up and walk around on his own.

Austrevich wanted to share the jokes with others, so Len and volunteers for Jokes4Miles have started an initiative to gather jokes for other children with cancer and have plans to continue in the future. Jeff Solin, who taught Austrevich in high school, said Austrevich’s desire to share his jokes exemplified his compassion.

“The cancer didn’t define him,” Solin added. “If you took the cancer away, you still have an amazing, amazing person that was selfless, fun to be around, helpful, caring and all that stuff.”

Booth said Austrevich never lost his temper or got angry throughout his battle with cancer. Instead of asking “Why me?” she said Austrevich would ask, “Why not me?”

Those who knew Austrevich said he wanted to study many subjects at Yale, including endocrinology, which he became interested in after the first round of treatments for his tumor. He was drawn to the flexibility of Yale’s curriculum when choosing between colleges.

When Austrevich’s cancer first relapsed, Len said he did not want to fantasize about his son’s major and career choices after Yale. Still, Len added that Austrevich was so excited about starting college that he even looked forward to the most minor details of moving to New Haven, like buying a microwave for his dorm room.

Mussman said she remembers how Austrevich’s treatment kept him from visiting Yale for Bulldog Days for the second time last spring. She and Austrevich were supposed to enroll together in fall 2011, and Mussman said she is still processing the fact that he never was able to experience Yale like she did.

Through an event on Facebook, students at Northside College Preparatory High School are coordinating wearing Jokes4Miles merchandise or anything orange, Miles’ favorite color, on the first day back to the school in 2013.

Miles is survived by his mother, father, stepfather and younger brother.