(CNN) -- The maternal grandmother of a 7-month-old Florida girl found hidden in a small cedar box under her baby sitter's bed says her daughter, who was charged in the case, is troubled and needs help.
Police think Chrystina Lynn Mercer gave Shannon Lee Dedrick to the sitter -- who is the baby's paternal aunt, Susan Baker -- and 10 hours later reported the girl missing.
"As confused as Tina is, I have to tell you, she has emphatically stated that she did not and would not ever harm her child," Mercer's mother, Kandis Boyer, said Thursday on HLN's "Nancy Grace."
Without elaborating, Boyer said she thinks her daughter "was manipulated into this situation."
Baker, whose home Shannon was found in, was also charged in connection with the incident, Washington County Sheriff Bobby Haddock has said.
The baby is in protective custody with the state and is in good health despite her ordeal, according to Boyer, who says she drove nearly 900 miles in 14 hours from Texas to Florida when Shannon disappeared.
According to Haddock, Baker took custody of Shannon from her mother on Saturday.
Boyer said her daughter told her she only let Baker care for the child, nothing more.
Asked why Mercer reported the child missing to police, Boyer said she did not know.
Boyer said her daughter has said "so many different things" and that "she seems to be very confused. That's what I've gathered from talking to her myself since I have been here from Texas."
She said her daughter has had counseling over the years, and "she's going to get the help she needs now."
Clothes and baking powder to hide the smell of soiled diapers were found inside the 2-foot-by-3-foot box.
Shannon had been inside the box for about half a day before authorities found her late Wednesday, but she might have been in and out of the box for several days, investigators said.