The Mount Laurel doctrine is of more than just professional interest to Tracy Siebold and Amelia Carolla.

As the New Jersey Supreme Court considers the state's latest affordable-housing case, the two lawyers - who are best friends - also have a personal stake in the matter.

His name is Benjamin Bono.

He's Carolla's 11-year-old son, and he has Asperger's. People with the condition, sometimes described as a "milder" form of autism, are often highly intelligent but can have difficulty reading social cues.

"This little guy became the face of who I was writing for," says Siebold, an attorney with the Ballard Spahr firm in Cherry Hill who filed a friend-of-the-court brief in the case. "Ben was more or less the inspiration."

Siebold's brief supports an appellate ruling, under review by the Supreme Court, that requires state oversight of how many affordable homes must be provided in each community. Municipalities have challenged those regulations, which sparked the appellate ruling.

Siebold submitted the brief on behalf of six New Jersey organizations that advocate for or provide housing for adults with autism or other mental or physical disabilities.

About 7,000 homes for people with special needs have been built in the state in the 29 years since the first Mount Laurel case. About 870,000 Garden State residents fit census criteria for the disabled.

Carolla hopes Ben, a straight-A student at the Lewis School in Princeton, will someday be able to work and live independently. "But there are a lot of children who don't have that possibility," she says. "Why shouldn't they have a fair shake?"

Advocates worry that many New Jersey communities would rather not have any housing for disabled people. Siebold found that 40 percent of the housing-discrimination complaints received by the state Division on Civil Rights involve the disabled.

"The housing that is available is so inadequate," Carolla tells me, as Ben - his homework done - entertains himself with an iPad at their Haddonfield home. "And there's such a long waiting list."

Two previous state Supreme Court decisions, often referred to as Mount Laurel I and II, as well as the New Jersey Fair Housing Act and the Council on Affordable Housing that was created by the act, seek to prevent municipalities from discouraging development of housing for people of low or moderate incomes. The disabled often fall into those groups.

Issues over how best to encourage construction of affordable or supportive housing have resulted in delays and litigation that have created "a de facto moratorium" on new projects, says Siebold, a Westampton resident whose practice focuses on land-use and affordable-housing issues.

"My firm does a lot of pro bono work, and when I was asked to do this, I was thrilled to accept," Siebold says. "This [issue] is personal to me."

Says Carolla, "Tracy has seen me change from having a child with special needs - how it affected me."

Carolla left the firm where she met Siebold 13 years ago and formed a practice specializing in special-education law.

"Ben requires a lot of patience, but he's also allowed me to appreciate the smaller, more important things in life, things that money cannot buy," Carolla says. "He has come a long way."

Siebold says she is pleased to be part of an effort "to make a difference and make affordable housing available for people like Ben.

"If I could do it for anybody," she adds, "it would be him."