The mother of three young boys whose father never brought them home after Thanksgiving in 2010 has filed a petition to have them legally declared dead.

A hearing on the petition, filed last June, is set to begin on Monday, The Associated Press reports.

Tanya Zuvers and John Skelton were divorcing in 2010 and Andrew, Alexander, and Tanner Skelton — 9, 7, and 5 — spent Thanksgiving with their father at his home in Morenci, Michigan, as CrimeOnline reported. When Zuvers didn’t hear from him about a pick up time, she went to his house and found no one at home.

Zuvers ultimately found Skelton in a nearby hospital being treated for a broken ankle, which investigators said came while he was trying to commit suicide. But the boys were never seen again.

Skelton told investigators multiple different stories about the boys’ disappearance, including claiming he gave them to an organization to protect them from their mother, who he claimed was abusive.

Police later tracked Skelton’s phone into Ohio at 4:30 a.m. on Thanksgiving morning, when it was turned off, then turned back on again 90 minutes later in Morenci.

Skelton was ultimately charged with unlawful imprisonment in the disappearance and sentenced to 10 years in prison. That sentence will be up in November.

Zuvers said in a statement when she filed the petition last summer that her decision to have the boys declared dead “did not come lightly and was definitely a difficult decision to make.”

“No parent wants to lose a child, but to have the courts step in and declare them deceased is just unfathomable,” she said.

Zuvers noted that all three boys would now be over the age of 18, if they were still alive “and all would have graduated high school, yet they have not been returned to me and are still missing.”