If not for Dale Nathan, two Lakeville teens missing for more than two years may never have been found and reunited with their father.

Not that Nathan was happy about that. About two months ago, he told the Star Tribune that the reunification was a "tragedy," alleging it was another example of corrupt courts putting children with abusive parents.

Nathan, a longtime attorney who became an outspoken critic of the family justice system, died of lymphoma Saturday. The Eagan resident was 81.

Nathan was born in Kentucky where he got his law degree, then moved to Minnesota in 1965 where he worked as an attorney. His sister, Barb Liebschutz, said Nathan began taking pro bono cases of parents who felt they were being treated unfairly by the courts.

His practice became controversial. By 2003 he had been admonished twice by the Minnesota Lawyers Professional Responsibility Board for what was described as harassing and frivolous conduct.

By then Nathan had spent 54 days in jail for contempt after refusing to tell a judge where a client was hiding her missing child. In another case, a Ramsey County judge got fed up with Nathan as he represented a woman trying to keep the parental rights to her two children. The judge ordered Nathan to stop harassing and threatening a social worker and therapist on the case, and not to make any details of the case public.

Nathan defied the order.

"Occasionally," Nathan explained at the time, "it is necessary to violate a court order or even a law in order to correct serious injustices."

In 2003, the Minnesota Supreme Court suspended Nathan's license, ruling it could only be reinstated if he swore to obey court orders.

Nathan refused.

He became a vocal critic of family courts, arguing they needed to be reformed due to a litany of cases in which judges wrongfully pulled children from loving parents. His platform and legal background often attracted parents who felt they too were victims of the courts. Among them was Lea Dannewitz, who met Nathan in 2010 when she was going through a divorce. Nathan spent hours helping her, and Dannewitz credits him with enabling her to see her kids again. Nathan also took Dannewitz to the State Capitol, where she told her story to lawmakers.

"I wouldn't be where I am if it wasn't for him," she said. "So many can say the same."

Another parent who sought his help was Sandra Grazzini-Rucki, who was fighting for custody of her five children, including her two daughters Gianna and Samantha. On April 19, 2013, the two girls ran away from their Lakeville home and went missing for two years. In March 2015, Nathan said that he witnessed Grazzini-Rucki help the girls run away that night.

Police later searched Nathan's home, which ultimately led to the girls being found in November at a horse ranch near Herman, Minn.

Nathan said that he broke his silence because he was worried about how the girls were being treated. He had hoped they would be reunited with their mother, but she has been charged with several counts of felony deprivation of parental rights.

The night before Nathan died, the ABC News program "20/20" aired a report on the Lakeville sisters featuring an interview with Nathan. Liebschutz said Nathan stayed alive just long enough to watch it.

"He was very pleased to be bringing to everybody's attention that there were mothers, fathers and children wrapped up in the court system," she said Tuesday.

Nathan is survived by a daughter, Chris-Ann Wilkoske, and two sisters, Liebschutz and Audrey Weinstein.

A graveside service is scheduled for 10 a.m. Wednesday at Temple of Aaron Cemetery in Roseville.