SAN FRANCISCO - San Francisco police are asking for the public's help in solving a cold case ---a double homicide that took place almost three years ago.
A homeless man and woman were shot and killed in the Mission neighborhood.
Police are now offering a $25,000 reward for information leading to the idenitification, arrest and conviction of whoever's responsible.
The sister of victim Lindsay McCollum said it's been three difficult years mourning and trying to get justice.
"My sister was an angel. She didn't deserve any of this," said Katie McCollum who spoke with us from her home in the Central Valley. She describes her sister as beautiful, funny, and intelligent.
"My sister has a family who cries about her every single day," said Katie.
The 27-year-old was shot and killed along with a friend named Eddie Tate known as 'Tennessee'.
Police and Lindsay's family are offering a reward for information leading to whoever's responsible.
"We're empty inside so please help us," said Katie.
Lindsay and Tennessee were living out of a box on 16th Street and Shotwell Street.
On December 18, 2016 at 8:45 p.m., someone walked up to them while they were inside and shot them.
A source told KTVU they were targeted and the motive is drug-related.
Katie said Lindsay's addiction to drugs started after a serious car accident: "When she was in the hospital, she got hooked on Oxycodone and other drugs. It happened after that accident."
Those who know 51-year-old Tennessee describe him as someone who offered what little he had to help others.
"Tennessee was beloved in the community. He would look out for people," said Kelley Cutler with the Coalition on Homelessness.
"No one should have to die on our streets, especially someone who was just making do with what they had," said Officer Robert Rueca with San Francisco Police.
Katie said she has holiday presents that she never had a chance to give to Lindsay that year since she was killed one week before Christmas; gifts that included warm clothes. "We were worried about her. It's so cold in San Francisco."
Katie said her family won't rest until whoever's responsible is brought to justice,"This heinous, senseless crime has destroyed my family. I know there's someone out there that knows something and we all urge them to come forward and give that information to the police.
Police said they have exhausted all leads in this case. They are offering a $25,000 reward. Lindsay's family is offering their own $5,000 reward.
Lindsay's mother wrote a tribute to her daughter. She asked KTVU to share it. You can read it here.