“Uplift this family. Uplift your own families. Hold your loved ones a little tighter,” he said on Twitter on Tuesday. “And to the family of Kamille, know that your pain, your anger, and your many questions will not be ignored. Your cries for help will not go unanswered.”

Kamille, who was known as Cupcake, was last seen around 8:30 p.m. on Oct. 12 at the Tom Brown Village Housing Community while attending a birthday party, according to a police statement on Oct. 15. She had been wearing a pink T-shirt with leopard print on it and leopard-print shorts with no shoes.

Dominic McKinney, Kamille’s father, told the local news station WVTM on Oct. 13 that his daughter was a “good little girl, she’s sweet, she’s real lovable.”

Her disappearance had been a “hard thing to swallow” because he had never been without her, he said, adding that he just wanted his daughter returned.

Calls to Mr. McKinney on Wednesday were not answered.

April Thomas, Kamille’s mother, also made an emotional plea for her return on Oct. 14, telling the local station WKRG that if anyone had seen her daughter, “just please just bring her back.”

Her voice breaking , Ms. Thomas asked why someone would take her daughter.

An Amber Alert was issued for Kamille, and CrimeStoppers offered a $20,000 cash reward on Oct. 16 for tips and information leading to the end of the investigation. Two days later, the police department released surveillance footage from the housing complex around the time Kamille was reported missing.

“We believe that this was something that they thought about and acted upon,” Chief Smith said regarding a possible motive while referring to Mr. Stallworth and Ms. Brown. “And they saw an opportunity to take a young child, which they did. And our further investigation will reveal whatever actions were taken after that.”