Ceianna and Brianna were sleeping with the same adult, their 30-year-old mother of eight, Rose Prescott.
Prescott, who could not be reached Monday, has given investigators conflicting accounts about what happened to Ceianna Saturday evening at the family's apartment in the 2900 block of N. 29th St.
She first told police that two cousins were baby-sitting Ceianna while she and three other children went to Chuck E. Cheese. According to a medical examiner's report, Prescott told police she came home shortly after 9 p.m., fed Ceianna about 11:30 and then placed her on her back on a living room couch with her brother, who turns 2 this month.
She then went to sleep on the hardwood floor in front of the couch, Prescott told police.
She then changed her story, according to the medical examiner's report, and told police that she had left Ceianna and the 1-year-old boy with a baby sitter, went to Chuck E. Cheese and picked them up at 9:30 p.m.
Finally, Prescott told police she had gone to a party and gotten drunk Saturday night. She did not remember when she picked up the children or even coming home. She told police it was possible she slept on the couch with the two children.
Investigators reported finding a blue plastic bag containing food on the floor, but no blankets or pillows. They found Prescott's car keys under the infant girl.
Prescott told police she woke up about 8:30 a.m. Sunday and her daughter was not breathing.
Delores Howard, who lives below Prescott, said in an interview that Prescott came downstairs screaming that her child was not breathing and asking her to call 911.
Howard said that as she called 911, she sent her 15-year-old son to Prescott's apartment to check on the child. Prescott, who Howard said was hysterical, ran from the house. She returned within a few hours, Howard said.
Howard said her son found the infant on her stomach, pressed to the back of the suede-like couch.
On April 17, 2008, Brianna Buchanan-Prescott died while sleeping with Prescott.
Prescott and four of her children were living with her grandmother at the time. According to a medical examiner's report, Prescott told police she placed Brianna in one of two twin beds pushed together in her room. Prescott slept with the baby in one bed, her then 1-year-old son in the other.
When she awoke, the baby girl, who lay on her side in the center of the two beds, had stopped breathing. She was pronounced dead at the scene.
"I don't know what to think," Cedric Buchanan, 34, the father of the two girls, said Monday.
He sat on a couch in his mother's living room, holding his son, the boy not quite 2 years old.
"I don't know what to believe," he said.