Outside her home in Terre Hill, Lancaster County, Sue Witman read text messages off her iPhone that offered congratulations to her family, including ones from numbers that she didn’t immediately recognize.

After more than 15 years, her oldest son, Zach, was released from prison on Tuesday.

“I couldn’t be happier,” Sue Witman said. “I’m the happiest that I’ve been in 21 years.”

She said she believes her son will have a decent life and be more successful than any other person in his position. She said she didn't think even he knows exactly what's next.

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On Oct. 2, 1998, Zach Witman, who was then 15, stabbed and slashed his brother, Greg, 13, more than 100 times at their home in New Freedom.

Zach was found guilty of first-degree murder and sentenced to life in prison without the possibility of parole. But following a series of legal developments, he accepted a plea agreement for third-degree murder: 15 years and 230 days to 40 years in prison. “Yes, I can say I killed my brother by stabbing,” he told the court.

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Sue Witman said her husband, Ron, and Jeff Stein, their private investigator, went to the State Correctional Institution at Smithfield on Tuesday.

At about 9 a.m., Zach Witman, now 36, pushed a cart that contained his belongings and walked outside the walls without any handcuffs or shackles.

“You can see the happiness that both he and his father shared, being able to embrace, to hug, and greet each other,” Stein said.

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Later, Zach ate French toast at a restaurant about 40 minutes from the prison. He then went to the new family home and met the dogs, Chyna, Truman and Mak, all miniature dachshunds, and Gibbs, a Havanese. Loved ones brought over some of his favorite foods, including shrimp and birthday cake.

Sue Witman said she didn't want to discuss the facts of the case. At one point, without elaborating, she said, “Zach took a plea to get out of prison.”

She said her son is going to move in with them.

He was not available for comment Tuesday.

He could go to school, his mother said, or work and attend classes at night. Zach Witman was a straight-A student and helped other prisoners obtain their GED diplomas.

Said Sue Witman: “He’s thrilled to be out.”

Contact Dylan Segelbaum at 717-771-2102.

Check out this photo gallery of the Zach Witman case: