LOUISVILLE, Ky. (WDRB) -- A Grayson County family makes a desperate plea for a teenage couple to come home as the sheriff say they're committing 'brazen and dangerous' crimes.

Tammy Martin holds on to the last texts and pictures she has of her son, 18-year-old Dalton Hayes.

"Last I heard from him was Tuesday at 5:48 p.m.," she said. "He texted me that he loved me and would call me soon -- and I have not heard anything else."

She showed us a picture of Hayes. He can be seen on a motorcycle with the girl Martin says she thought was his 19-year-old girlfriend, Cheyenne Phillips.

"He's told me that he loves her," she said. "He actually bought her an engagement ring."

It turns out Phillips is only 13-years-old. Martin claims her son did not know, and that there have been other lies.

"When she first told my son that she was pregnant, she shouldn't have been but three weeks, and she sent him an ultrasound picture via a text -- and that was not her pregnancy picture," Martin said.

The couple hasn't been seen since Jan. 4. They escaped police in Breckenridge County a few days later and officers thought they may have been staying with friends.

Grasyon County Sheriff Norman Chaffins said, "I know Dalton personally and I will tell you that Dalton is a good boy, just making some stupid decisions."

The Sheriff's search became more dire on Sunday Jan. 11. He said the couple stole a vehicle from a house on Clark School Road in Clarkson, Ky, crashed through a fence about a mile away, ditched the van and ran off through the woods. 

Deputies searched into the night but couldn't find them. A few hours later, another vehicle was stolen nearby. Chaffins believes the couple may still be in it: a red 2006 Toyota Tacoma four-wheel drive extended cab. 

"We don't want the situation to become worse than it already is," said Chaffins. "Our biggest fear is they steal another vehicle, a law enforcement agency will get into a pursuit of that vehicle and obviously the outcome is usually not good."

The couple may still be in Kentucky. Chaffins said Hayes is currently only charged with custodial interference. When asked about the underage relationship he said, " We're not worried about that right now."

Hayes is described as 5'10", 175-180 pounds. Phillips is described as 5'1", 100 pounds.

Since the texts have stop coming, Hayes' mother is making a public appeal. 

"Please come home,'" Martin said. "We love and miss you all and we need you home and safe. Come home before someone is really, really, hurt."

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