18-year-old Cristian Dominguez Aguilar was killed by a man who believed the mother of his child and Aguilar were in a relationship.

FONTANA (CBSLA) — The family of a man who unwittingly found himself in a deadly love triangle were mourning him Friday night, asking the public to help them properly say their good-byes to their young loved one, and trying to figure out how something like this could happen to someone who had so much ahead of him.

Photos, candles and cards lined the parking lot of the Fontana 7-11 where Cristian Dominguez Aguilar was killed Wednesday night, the victim of hit-and-run prompted by what police believe to be sheer jealousy.

“I’ll miss him telling me that when everything would get hard, we were gonna make it,” Aguilar’s sister-in-law Jessica Milan told CBS2 News as she choked back tears.

The 18-year-old was struck by a truck allegedly being driven by John Nieto of San Bernardino. He has a child with Elisabeth Mancilla of Rialto, Aguilar’s coworker who regularly gave him a ride home. Mancilla, 20, dropped Aguilar off at at the convenience store before Nieto hit him with his vehicle.

Police say Nieto, 20, erroneously believed Mancilla and Aguilar were in a romantic relationship. After Nieto struck Aguilar, he abandoned his car and was picked up by Mancilla down the street. They then drove to Rialto.

Nieto has been charged with murder, and Mancilla has been charged as an accessory to murder.

Aguilar’s family, including his father, came from Mexico to say “good-bye” to him and to demand justice.

“My family is destroyed,” said Aguilar’s brother Armando. “All his family is in Mexico, so you can imagine how hard it is.”

His family said Aguilar had a lot to offer the world.

“The most that I’ll remember of him is his big heart,” Milan said.

The family has started a GoFundMe page to raise money for Cristian’s burial and will host a car wash Saturday, November 25 at the Big Lots located at 17575 East Foothill Boulevard, just down the street from where Aguilar died.