When they couldn’t reach their son, a Maryland couple made the 600-mile drive through the night to their son’s home in Atlanta. Timothy Cunningham’s vehicle, wallet, phone and his beloved dog were inside his northwest Atlanta home when his parents arrived.

But their 35-year-old son was nowhere to be found. Cunningham, who led the Division of Population Health National Center for Chronic Disease Prevention and Health Promotion for the Centers for Disease Control and Prevention in Atlanta last spoke to his family Feb. 12. Two weeks later, the search to find him continues.

“We will be here indefinitely until Tim returns. And we’re expecting him to return, that’s our prayer,” Cunningham’s mother, Tia-Juana Cunningham, told The Atlanta Journal-Constitution on Monday. “There are a lot of people praying for him nationally, and that’s how we maintain our spirit and faith.”

Cunningham spoke with his mother by phone at 7 a.m. Feb. 12, she told Atlanta police, according to a incident report released to The Atlanta Journal-Constitution. After that, her calls went unanswered.

Timothy Cunningham has not been seen or heard from since Monday.

“Mrs. Cunningham advised that when she called his job, they told her that Mr. Cunningham called out sick on Monday,” the police report states. “Mrs. Cunningham said after she called him several times and could not get in touch with him, she decided to drive to his house from Maryland.”

Cunningham, a Morehouse College and Harvard University graduate, does not have a history of mental illness and it is unusual for him to not be in contact with his family, his mother told police. Tia-Juana Cunningham told police her son was upset about a promotion and she was concerned about his behavior. She declined to discuss her son’s promotion Monday, citing the ongoing police investigation.

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Timothy Cunningham’s disappearance has made national headlines in recent days, and on Monday, the CDC said his colleagues are hopeful he returns home.

“Dr. Cunningham’s colleagues and friends at CDC hope that he is safe,” a CDC statement released Monday said. “We want him to return to his loved ones and his work—doing what he does best as a CDC disease detective—protecting people’s health.”

Timothy Cunningham was born in Montgomery, Ala., and lived in the Philippines from age 3 to 5 because of his parents’ military careers, his mother said. The family later relocated to Maryland, where Timothy grew up before he attended Morehouse for his undergraduate degree. Cunningham later earned two graduate degrees at the Harvard T.H. Chan School of Public Health. In November, The Atlanta Business Chronicle named Cunningham to its “40 Under 40” list for his accomplishments.

“He set his goals and he achieved them,” Tia-Juana Cunningham said. “He’s always been goal-oriented.”

But her son’s disappearance makes no sense, and it’s concerning that his dog, Mr. Bojangles, was left alone, Cunningham said.

“He never leaves Bo unattended,” Cunningham said. “Even when he goes on trips, he makes special arrangements.”

Atlanta police Officer Donald Hannah has said investigators have found no evidence of foul play, but the investigation into Cunningham’s disappearance continues.

Cunningham’s family has partnered with Crime Stoppers of Greater Atlanta to offer a $10,000 reward for information that leads to an arrest and indictment in this case. Information can be submitted anonymously to the Crime Stoppers Atlanta tip line at 404-577-TIPS (8477) or online at www.crimestoppersatlanta.org. Friends have created a Go Fund Me fundraising page to assist with the reward fund.