The mother, Victoria Purcell, went out of town for the weekend, and when she got back, the teen and the child were gone.
"I cry every night," Purcell said. "I'm trying to deal with it."
Purcell says she suspects her daughter's babysitter is using the infant for bait.
"Her niece says she got some boy in Alabama that she got him thinking that she was pregnant for him, and she wants him back so get got him thinking it's their baby," Purcell said.
Authorities have posted Saniya Purcell's and Griner's pictures nationwide. Hoke County deputies tracked the two to Columbus Georgia.
"We found out that the 17-year-old was actually taken to the bus station in Fayetteville, she got on a bus headed to Georgia with the baby," Hoke County Sheriff's Department Capt. John Kivette said.
Purcell says last Wednesday Griner ask if she could keep the baby girl for two weeks, Purcell refused, but later accepted the teen's offer to babysit for the weekend.
"I was like, 'Did you tell me you was taking my baby to Georgia?', she said 'Yeah,' I was like 'No you didn't'," Purcell said. "I was telling her you need to bring my baby back to NC ASAP and she hung up on me."
Whatever the reason, authorities are now treating it as a criminal case. Late Tuesday, Hoke County Sheriff Hubert Peterkin ordered his investigators to take out arrest warrants charging the teenage babysitter with first degree kidnapping.
Hoke County officials have not put out an Amber Alert for the pair because they don't believe Griner intends to hurt the infant. Amber Alert guidelines say a child must be believed to be in danger in order to put out an alert.
"At this point there is no reason to believe that the baby has been harmed, however this is a serious case and we are treating it as such and doing everything we possibly can to get the baby back home safe," Kivette said.
Still, the National Center for Missing and Exploited Children has the case up on its Web site - calling it a non-family abduction - and is asking people to be on the lookout for the pair.
Anyone who has any information is asked to call the Hoke County Sheriff's Office at (910) 875-5111.