The 25-year-old was reported missing on August 25 after he didn't show up to class in Bloomington, Ill., for several days.
Officials said a male body was found on Sept. 4. Today, the LaSalle County coroner positively identified the body as Day using DNA testing and comparison. The cause of death is currently unknown, pending further investigation and toxicology testing.
His family is asking for the public's help to find out what happened to him. Day's cousin Eriel Davis spoke with ABC7 Chicago Friday morning.
"What's obvious is none of us are holding up well at all," Davis said. "I didn't sleep well last night. My auntie didn't sleep well last night, his siblings didn't, my grandmother didn't, none of us did. So, it's a really hard time for all of us."
Davis said their mothers are sisters and Jelani was more like a brother to her.
"He's just always alive for the party. There's never a dull moment with Jelani. He was always outgoing and always making everything fun, he had a really great spirit," Davis said. "None of this makes sense. We're all trying to piece it together, which is why we need the help with the FBI. Jelani would never just disappear on his own. He loved his dad to the core. He was a bone marrow match for his dad. His dad has cancer and Jelani would always come here and visit him, sit with him, pray with him, talk with him. Jelani was just an awesome man. He was excited about being able to help his dad."
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According to officials, his family last spoke to him on Aug. 23, and was last seen on campus on Aug. 24. Officials said his car was found in Peru, Ill., on Aug. 26.
Based on findings by Peru police, when they found his car, searches were conducted in Peru, but Day was not found. On Sept. 4, another search recovered male remains floating near the south bank of the Illinois River, approximately a quarter-mile east of the Illinois Rte. 251 bridge.
The Danville native had been in Chicago to visit family just a couple days before he went missing. Day was a Masters student at ISU studying speech pathology and hoped to become a doctor.
His family is heartbroken, and demanding answers about what exactly happened and how the investigation was conducted, especially after seeing the resources put into the disappearance of Gabby Petito.
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His mother spoke to the I-Team Wednesday, desperate for answers.
"He's educated. He's a productive citizen. And I can't get nobody to look for my son, to provide us with those same resources, with that same help. And that's all I'm asking for," Carmen Bolden Day said.
Investigators said they were able to identify Day's remains through forensic dental identification and DNA testing. Day's cousin, Eriel Davis, said he came to visit family and friends in Chicago just two days before he went missing.
She said nothing about his disappearance and discovery makes sense.
"His dad actually has cancer and Jelani is the bone marrow match for his dad, and he would never abandon his father like that," she said Wednesday when speaking with ABC7 Eyewitness News. "He would come here in Chicago and visit him at Northwestern hospital, sit with him, you know, encourage him, pray with him."
The family is devastated, but said now is the time they need answers. They want the public's help to find out what happened to Jelani Day, and are asking anyone with any information to contact police.
Police said they are continuing to investigate Day's death.
Full Statement from Jelani Day's family
There are no words to clearly communicate our devastation. We learned this morning from the LaSalle County Coroner the deceased man found in Peru, IL on Saturday, September 4 is Jelani. Our hearts are broken.
We ask that you continue to pray for our family during what will be very hard days ahead. Throughout these 30 days, our very first concern was finding Jelani, and now we need to find out #WhatHappenedToJelaniDay
At this moment there are more questions than answers surrounding Jelani's disappearance and death, and that is where we will focus our energy. As of this moment, we do not know what happened to Jelani and we will not stop until we do.
This week we learned new evidence has been discovered and police are working on new leads related to Jelani's disappearance. This case is not closed and the investigation is not over.
We STILL need people who have information to come forward. If you know anything about what happened to Jelani or had contact with Jelani in the days and weeks before his disappearance, please contact Bloomington Police Detective Paul Jones at (309)434-2548 or email him at firstname.lastname@example.org.
We have also hired JAB Professional Services to assist the police. Information regarding Jelani's disappearance can be emailed/texted to Beliveaups@yahoo.com 618-223-0044 (C) The family is offering a $25,000+ cash reward. https://gofund.me/8ee08e46
Thank you to every single person who has thought about, prayed for, talked about, and searched for Jelani. The love you've shown our family has sustained us and we will definitely need you even more in the days to come. We love each and every one of you for making Jelani's story personal.
We will continue to share updates on Jelani's case as information becomes available.