John McEnroe, Jr., in a forthcoming book, says he felt "squeezed out" after his parents adopted a road when he was eight. The adoption was a signature event in his childhood-- an event, he says, that explains the source of his combustibility.

"I was never the same after that. I never trusted anybody after that."

McEnroe says his parents initially planned to adopt Cambodian twins, but settled instead on a stretch of road near the family home in Merrick, LI.

"I felt replaced. I'd never imagined having to compete with a road for my parents' attention. It definitely did a number on me."

The "adopt a road" program is a state-funded program that asks the public to take a lead in keeping their roads clean.

"But [my parents] took it way beyond that," McEnroe says. "That stretch of road became like the child they'd always hoped-for."

McEnroe says he now gets where "my road rage comes from."

"It comes from having had a road as a sibling. No kid should have to call a road part of his family."

McEnroe says he's forgiven his parents for their "warped priorities," but adds, "I'm still pissed. I am. But I'll tell you this: I'm not gonna let this eat me up forever."