The family, crushed by the death of one twin, is adamant the other is innocent.
"There's no way, shape or form that my brother was even in that house," said the boys' older sister, Diane Lewis, who lives two doors from where the shooting happened. "He would never put my mom in harm's way whatsoever - she didn't raise killers or criminals."
Derris is charged in juvenile court with being an accomplice to aggravated murder, aggravated robbery and kidnapping. Because he turned 18 two weeks after the shooting, prosecutors are seeking to have him charged as an adult.
Authorities won't say what Derris Lewis is accused of doing. They say the motive that night was robbery but won't elaborate.
"There were multiple people that entered and anyone who entered the premise is an accomplice," said Franklin County Prosecutor Ron O'Brien.
Derris Lewis' public defender, Libby Hall, declined to comment. The attack happened just after midnight on Jan. 18 in a tough neighborhood of small homes on the city's north side.
The twins' mother, April Agee, was asleep on a couch in the front room of her house, the only place she could lie comfortably because of her multiple sclerosis and cerebral palsy.
Dennis was asleep in the next room with the door shut. Derris had moved out a few weeks earlier and was staying with his girlfriend elsewhere in the city.
Agee says several men wearing black masks, white shirts and white sneakers entered the house, put a gun to her head, demanded money and asked who else was in the house.
"They kept saying 'Where's the money, where's the money,' with a .45 up to my head," Agee recalled at her daughter's home. She doesn't know who the men were.
"I couldn't do nothing but be still. God say 'Be still,' and I was, but my son started fighting them," she said.
Agee, 47, said one of the men kicked Dennis' bedroom door in and struggled with him. She heard someone yell "He's too strong," then the sound of a gun shot.
The family says there was no forced entry. They don't know if the front door was locked before Dennis and his mother went to bed that night.
The robbers did not take $235 in cash in an envelope in Dennis' room, money he was saving to visit Florida State University, which he planned to attend.
The family believes police made a mistake with the palm print.
Derris' prints were in the room because he had lived there until recently, Diane Lewis said.
And she recalled there was blood everywhere in the destruction of the bedroom. "It was Dennis' blood on top of Derris' print," she said, her voice rising.
Unlike DNA, fingerprints can differentiate between identical twins. "It is well established that identical twins can and do have different fingerprints," said professor Jay Siegel, director of the forensic and investigative sciences program at Indiana University-Purdue University Indianapolis.
The twins' father left when they were 2. Their mother does not work because of her disabilities and gets by on government assistance.
In school, teachers called the boys two peas in a pod.
At East High School, Dennis played the trombone in the marching band; Derris is the lead drum major. Both ran track, played volleyball and tennis. Last fall, Derris played the wizard in the school's production of "The Wiz" and Dennis played the scarecrow. Both were head cashiers at a Giant Eagle grocery store.
They sang the gospel song "I Told the Storm" at a ninth-grade talent contest. Derris and a cousin sang the song at his brother's funeral.
After Dennis died, Derris moved in with his sister to help care for their mother. Diane Lewis said her brother was distraught and didn't talk much about what happened. He got up early each morning to see a teacher who was helping him prepare for his college advanced placement test.
He was charged Feb. 13. He took the advanced placement test in jail, while awaiting an April 30 hearing. He's tutoring other boys and hoping to get out in time to graduate June 5. He plans to attend Ohio State University.
The family wants to know why no one else has been arrested.
"We cannot grieve over Dennis because they took Derris," said the boys' aunt, Paula Lewis, now a full-time caretaker for her sister. "He's an innocent child. We miss him. We love him. We just want him home."