Father of Slain Girl, 13, Shares His Regrets: 'I Wish I'd Wrapped Her Up, Hugged Her'

The distraught father of a 13-year-old girl allegedly killed by a college student she met on social media says he is filled with regret.

"I wasn't there for her when she needed me," David Lovell said, clutching his daughter's stuffed panda as he appeared on "Dr. Phil."

Read: FBI: Virginia Tech Student Charged in Abduction and Killing of 13-Year-Old Girl 'Excited' About Plot

Lovell knew his daughter was having inappropriate contact with men on social media sites and tried to stop it, he said.

If he had it to do over again, Lovell said, "I would have taken her phone. I would have locked her down.

"I would have wrapped her up and hugged her and told her you are so loved, you don't need to be worrying about all these boys. You're beautiful as who you are," her father said.

David Eisenhauer and Natalie Keepers, both 19, have been charged in connection with the killing of Nicole Lovell, who climbed out her Virginia bedroom window and was never seen alive again by her parents.

Her body was discovered three days later, on Jan. 30, in North Carolina.

Read: College Track Star Charged in Slaying of 13-Year-Old Transplant Patient

Eisenhauer has been charged with murder. Keepers has been charged with being an accessory and helping to dispose of Lovell's body. Both are being held without bail.

"My daughter would have fought like a wildcat," Lovell said. He noted that Keepers appeared to have a scar on her face and said he thought Nicole may have been responsible for that.

Watch: Heartbroken Mom of Murdered 13-Year-Old Remembers Daughter