It has been a year since Liliana Moreno, 43, and Daniela Moreno, 9, vanished.
To mark the moment Moreno's family members are set to hold a vigil Tuesday outside Castano's home in Doral.
"All day we're thinking if they're eating," Eduardo Moreno, said about his missing sister and niece.
Gustavo Castano, the little girl's father, was the last person to see them when he dropped the pair off on Florida’s Turnpike near Okeechobee Road.
Shortly after, he tried to kill himself.
Miami-Dade detectives had called Castano a person of interest but he was never arrested and is not facing charges.
Castano's attorney did not respond to requests for a comment.
Moreno's family said that he hasn't had contact with them since the disappearance.
Anyone with information about the whereabouts of the mother and daughter are asked to call Crime Stoppers at 305-471-TIPS.