FORT LAUDERDALE, Fla. -- A convicted child killer who was given a second chance at life will now spend the next three decades in prison for violating his probation.

Lionel Tate was sentenced Thursday to 30 years behind bars for allegedly robbing a pizza deliveryman last May.

Last month, Judge Joel Lazarus ruled that Tate was competent enough to understand legal proceedings against him despite new revelations that Tate may be suffering mental illness from abuse as a child.

Lazarus said after listening to testimony from three psychologists that he "had heard nothing" to indicate that Tate was mentally incompetent.

At the time, Tate was represented by attorney Ellis Rubin, who asked to withdraw as the teen's attorney because he said his client wouldn't follow his legal advice.

"I regret that this 19-year-old young man will not abide by my 55 years of experience," Rubin said. "…I wish Lionel Tate the best of luck with his fifth attorney and may our paths cross again somewhere over the rainbow."

That rainbow might not come until 2036.

Previously, Rubin filed a motion asking for Tate to be declared incompetent based on a letter Tate had sent Lazarus asking to withdraw his guilty plea for robbing a pizza deliveryman.

Tate has already admitted to possession of a firearm, which brought the 30-year sentence.

Tate was convicted of killing 6-year-old Tiffany Eunick in 1999, when he was only 12. His lawyers initially claimed the killing was an accident caused when Tate imitated pro wrestling moves he'd seen on TV.

In court Thursday, Kathleen Grossett-Tate asked the judge for mercy when sentencing her son, saying it had been "a long, long fight for us."

Last month, psychologist Donna Weiss, who examined Tate in April on an order from Lazarus, revealed that Tate could be suffering from "post-traumatic stress syndrome" because of abuse he allegedly suffered at the hands of his mother. Weiss testified that Tate told her he was severely abused from the time he was very young until about age 12 by Grossett-Tate, who is a Florida Highway Patrol trooper.

Tate's new attorney, H. Dohn Williams, didn't back down from that claim, repeatedly blaming Grossett-Tate for her son's legal troubles.

"We can only speculate what this court's ruling might have been if his mother had not obstructed this court from hearing all the evidence," Williams said.

Family friend Bobby Duncan told Lazarus that she didn't think he deserved the 30-year sentence "because he's not mature enough. He just deserves another chance."

But Lazarus didn't seem to think so, saying Tate has shown "disdain and disrespect" for the law and that he has "run out of chances."

Tate, who was the youngest person in modern U.S. history to receive a life sentence for Eunick's murder, didn't speak in court, but Williams said he intends to fight the robbery charge.

That trial is scheduled to begin Sept. 18. Tate faces life in prison, in addition to the 30 years, if he is convicted.