The U.S. Marshal Service recently announced a $5,000 reward to anyone who aided in the direct arrest of Fields and Diaz, who were wanted in the death of a 4-year-old girl, police say.
The federal authorities and the local police have together launched a manhunt for Candice Renea Diaz, 24, and Brad Edward Fields, 28.
Michigan State Police and the Child Protective Services agency are now assisting with the crime investigation.
Officers and the girl's family tried to revive her with CPR, police said, but she had to be rushed to a hospital in Ann Arbor, where she was eventually pronounced dead.
Two days later, the Washtenaw County Medical Examiner ruled the child's death as a homicide with evidence of multiple traumatic injuries and signs of Battered Child Syndrome.
Donations were being accepted by Gabrielle's family at a Go Fund Me page.
"She didn't have to pass the way she did, but I hope we get justice for her really soon", Barrett said.
"We didn't know. We would have gone" and removed her from the home, he said.
Gabby was found unresponsive and with burns on her body by family members at the Rawsonville Woods mobile home community in Sumpter Township on New Year's Day.
Pictured, Michigan toddler, Gabby Barrett and her biological father, Kyle Barrett. Grandfather Jerry Barrett noted that it was hard to grieve because the family could not put her to rest. "She would run around the house when we had her, always with a big ol' smile on her face".
Police told WDIV News in Detroit that the home where the girl was found was full of animal waste and contained guns and drugs.
Both were charged, yet Child Protective Services weren't summoned until Diaz's four-year-old daughter suffered a horrific death.
Police say Diaz and Fields are driving a 2002 black Chevy Cavalier with the MI license plate of DTR1854. Officers had to storm the home on May 20, 2016, after receiving a report of a gunman barricaded inside following a domestic assault. Fields was arrested on domestic violence charges but Diaz later told police she didn't want to press charges.
This is not the first time Diaz and Fields have been in trouble.