HOPATCONG, N.J. (CBSNewYork) — A New Jersey mother issued an emotional plea Monday for the safe return of her two sons who have been missing for more than a month.

“I’m trying to find my boys Parker and Jaxon,” Sandra Hughes Dohm said.

Dohm said her ex-husband took the boys and vanished.

Dohm made a tearful public plea to help find the boys, at one point turning away from the cameras to collect herself, CBS2’s Alice Gainer reported.

She then issued several messages to them: “No matter what your dad is telling you, you need to know that we are looking for you, and we need you to come back home to us.”

Dohm last saw 7-year-old Jaxon and 8-year-old Parker on Feb. 3. Their father, 36-year-old Kristopher Dohm, of Hopatcong, was supposed to return the boys on Feb. 9 after asking for a visitation extension.

“He had told Ms. Dohm that his father was dying in Nevada and he asked for a few extra days if he could fly out there with the boys so they could visit with their ailing grandfather,” said Sussex County Prosecutor Francis Koch.

But the boys were never returned to their mother’s home in Landing, and investigators said it turns our their grandfather wasn’t ill. It was a lie.

They said even the flight information Dohm provided her was fraudulent.

Dohm is diabetic and requires daily shots of insulin. Parker has asthma.

The family doesn’t believe he would hurt the boys, but they’re stumped as to why he took them.

The couple had an amicable divorce back in 2012 and shared joint custody.

Sandra Dohm said her sons had a good relationship with their father.

“no indication he would do this,” she said.

Police said the trio may be traveling in a grey 2009 Nissan Pathfinder and all three may now have shaved heads.

Jaxon has a birthmark or mole on his chin. Parker wears glasses. Kristopher has a tribal band tattoo on his right arm and a tattoo on his left leg.

“Parker and Jaxon, I want you to know I love you and I miss you and I’ll never stop looking for you no matter what,” Sandra said.

The last time the car was seen was back on Feb. 6 as it traveled through Maryland. Investigators said there’s been no cell phone movement to track, and that they could be anywhere in the country.