He said he did not know whether the teen had returned to live with his mother, who lives in the apartments, or was living with another relative and just visiting his mother when Sida went missing.
Sida's mother, Dahabo Abdi, told Dallas-Fort Worth television station KTVT that she did not know the suspect.
As the family gathered outside the apartment Thursday, neighborhood children gave Sida's mother handwritten notes expressing affection for the child. Some read the notes aloud, including one that read, "You were just an innocent kid."
Muhammad Elmi, the child's uncle, told Dallas-Fort Worth television station KXAS that the family never expected such a tragic outcome.
"We expected to see him alive — you know, coming back to the house smiling, happy."