The sophomore from Humble was a 2016 graduate of Atascocita High School, where he played on the tennis team.
His family shared a photo with Eyewitness News, but said they would not be making any comments as they grieve and try to learn more about what happened.
Ellis was found unresponsive at the apartment complex late Monday morning. Within an hour, he was pronounced dead.
His high school friends, many away from home at different colleges, learned of the sad news through social media. Will Jackson, who now attends Texas Tech, played tennis with Ellis in high school.
"He was always a really funny guy. A serious guy in the classroom. You just don't expect it to happen to someone you know," said Jackson. "I'm definitely thinking of [his family] tonight."
Preliminary findings indicate alcohol may have been a factor in his death, but San Marcos police are awaiting results of a toxicology tests.
Ellis was a pledge of the Phi Kappa Psi fraternity at Texas State University. Police said the fraternity had a social gathering on Sunday, hours before Ellis' body was found.
Students at Texas State were shocked to learn of the death.
"We're all here to learn, all here to better ourselves, and to have someone die in the process of doing that, with or without alcohol, should be a kind of focal point and focusing on what's going on here," one student said. "What's really the attitude we want associated with our university?"
A candlelight vigil will be held at Texas State University tomorrow at 7 p.m.
Texas State University President Denise M. Trauth has suspended all Greek fraternity and sorority chapters at Texas State as a result of the tragedy.
Trauth's office released the following statement this afternoon:
As president of Texas State University, I am deeply saddened by the tragic death of one of our students who attended an off-campus social event on Sunday evening hosted by members of a university fraternity. Following a call from friends, officers with the San Marcos Police Department found Matthew Ellis, a Phi Kappa Psi pledge, unresponsive on Monday morning at an apartment off campus. He was pronounced dead after EMS personnel were unable to revive him. My thoughts are with his family, friends, and the Texas State Community.
As a result of this tragedy, I have suspended activities of all Greek fraternity and sorority chapters at Texas State. These chapters are prohibited from holding new-member events, chapter meetings, social functions, and philanthropic activities until a thorough review of the Greek Affairs system is completed.
I have asked Dr. Joanne Smith, Vice President for Student Affairs, who has responsibility for the Greek Affairs system, to immediately initiate this review and propose recommendations for reinstating fraternity and sorority chapters that demonstrate a commitment to the core values of Texas State and the ideals established by their respective national organizations.
It is imperative that our entire university community develop a culture that places the highest priority on the safety of its students, faculty, and staff.
Denise M. Trauth
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