But who, exactly, are the soulless fiends behind Na'illa's nightmarish kidnapping?
A law-enforcement source told the Daily News that it appeared that a man and two women were involved in the bizarre crime, including the woman who took Na'illa from Bryant Elementary School in West Philadelphia on Monday morning after claiming to be the girl's mother.
The suspects' identities, however, remain unknown. The Fraternal Order of Police Lodge 5 is offering a $5,000 reward for information that leads to the suspects' arrest and conviction.
Capt. John Darby, the head of the Philadelphia police Special Victims Unit, said it was clear that Na'illa wasn't a random victim. The woman who abducted the little girl went directly to her classroom, after ignoring a school worker's instructions to go to the main office, and asked for the child by name, Darby said.
"She said she was taking [Na'illa] to breakfast," Darby said of the female kidnapper, whose face was covered in Muslim garb.
Darby said the woman was a "stranger" to the little girl, but Na'illa's relatives said they believe that the kidnapper is someone who knows the family.
"Na'illa's very smart. She ain't gonna walk away with a stranger," said Sharif Ali, the girl's uncle. "But she shouldn't have got out the door anyway," he added, noting that school officials didn't check the kidnapper's identification.
"She just said she thought it was her aunt that was taking her," Asim Abdur-Rashid, Na'illa's grandfather, told NBC 10. "But we don't know who it was."
Danielle Robinson, the little girl's aunt, said Na'illa stayed home from school because of an illness on Thursday and Friday, and arrived late to school on the day she was kidnapped.
"It had to have been somebody who knew the kids would be back at school Monday," she said.
Even if the kidnappers know Na'illa's family, their motive is still shrouded and mystery.
Piecing together the details of the little girl's ordeal was proving to be a slow, painstaking endeavor for investigators.
"Keep in mind, folks, that this 5-year-old's world has been turned literally upside-down in the last 24 hours," Darby said Tuesday morning. "So we have a fragile victim here, a sensitive age. We have to proceed slowly."
The law-enforcement source said that it appeared Na'illa was taken to a house at some point after she left Bryant Elementary, and that a man removed her clothes.
She was blindfolded and then hidden under a bed, the source said.
Na'illa was later dropped off at a playground at 69th Street and Patterson Avenue, the source added, and told by the kidnappers to scream for help and tell whoever found her to call police.
Upper Darby Police Superintendent Michael Chitwood said he got a call about 4:45 a.m. notifying him that Myers, the passer-by, had found the little girl after hearing her cries for help while he was walking to a nearby train station.
The Good Samaritan said he asked the little girl where her parents were.
"She said, 'I don't know. Somebody was chasing me. I ran,' " he said. "She said she came from South Philly. I knew something was wrong, because I knew she couldn't have run from South Philly."
"In my opinion, based on my experience, and we see it across the country, you're very fortunate to be abducted and found alive," Chitwood said. "She's a very lucky little girl."
Na'illa was taken to Children's Hospital of Philadelphia, where she was examined for injuries and potential signs of sexual assault.
Darby said it appeared that she hadn't been assaulted, but investigators asked that the girl be interviewed by specialists at the Philadelphia Children's Alliance to see if they could learn more about what she experienced.
Na'illa returned to her South Philadelphia home in her mother's arms shortly after 2 p.m. Tuesday.
"We wanted her back, and we got her back. Thank you," Ali, the girl's uncle, said. "Now we're all just coping with the situation. I pray that nobody else's child goes through this."
The family had no big celebration planned for her return. Instead, Ali said, "we'll stay home and all pray, pray together, embrace her and treat her like she never left."
Anyone with information on Na'illa's kidnappers should contact the Special Victims Unit at 215-685-3251.
On Twitter: @dgambacorta