NORTH PORT, Fla. (WFLA) — The family of a woman who went missing during a cross-country road trip issued a statement Tuesday asking her boyfriend to cooperate with the investigation into her disappearance.

Gabby Petito, 22, was traveling with her boyfriend in their van when she disappeared. Her family believes that she was last seen with him in the Grand Teton-Yellowstone area. WFLA has chosen not to name the boyfriend at this point in the investigation.

Petito’s family released a joint statement saying her boyfriend “refuses to help.” In their statement, her mother and father said he should not “remain in the background” as several agencies, including the FBI and local police, continue searching for her. They say he’s back home in Florida and has a lawyer.

The van the couple was traveling in was also found back in Florida at the boyfriend’s parents’ house. Law enforcement towed the van away to be processed as evidence.

“The Schmidt and Petito family are going through the worst moments of their lives,” the families of Petito’s mother and father said in their statement. “Their beautiful 22-year-old daughter is missing, and the one person that can help find Gabby refuses to help.”

An attorney for the boyfriend’s family released a statement Tuesday saying the family would be “remaining in the background at this juncture and will have no further comment.”

“[He] is refusing to tell Gabby’s family where he last saw her. [He] is also refusing to explain why he left Gabby all alone and drove her van to Florida,” the statement from the Petito’s family said. “These are critical questions that require immediate answers.”

According to the statement released on behalf of the boyfriend’s family, they were aware of the search around Grand Teton National Park in Wyoming.

“It is our hope that the search for Miss Petito is successful and that Miss Petito is reunited with her family,” the statement from the boyfriend’s family said.