Bryan Nevins looked like a young man, but to his mother, he was a baby.

"He had a man's body, but he never grew up," said a tearful Diane Nevins, speaking from the home in Oceanside, N.Y., that she shares with her husband, a retired New York police officer.

Her severely autistic 20-year-old son, who died after being left in a hot van at the facility where he lived near Langhorne, had the mental acuity of a 2-year-old, she said.

"He was helpless."

But right now, his mother does not want to know the details of his death or who may be at fault. She wants to hold on to his beauty.

"He was a sweet little boy. He was very, very loving," said his mother. "People don't think autistic kids are loving, but he really was."

Bryan was a triplet, and his brother, Billy, is also autistic and also lived at Woods Services, a campus of 700 residents. His parents withdrew Billy Saturday night, the day his brother died of hyperthermia after a counselor allegedly left him in a hot van.

Nevins said she did not know if her son would - or could - have opened the doors of the van, where he was found lying down in a backseat.

"They had child locks on those doors. If you told Bryan to stay, that was what Bryan would do."

Though he could walk, he could say only a few words: Pizza. Pasta. Cookie.

"He loved to eat. He was a big eater."

Bryan was very close to both his siblings, but he and Billy were inseparable.

"He and his brother were the favorites everywhere they went," said his mom.

She has not told Billy that Bryan is dead, but said Thursday that she would talk to a psychiatrist about how to tell him.

Bryan, she said, was a very happy person.

"He loved it down there. He loved to walk in the woods. Perpetual motion. He loved to go, period. Bryan really loved to go."

She saw him a week and a half before he died. Her sons came home every other weekend and for holidays. Their sister, Kelly, did not suffer from the neurological disorder.

Nevins said she could not bury her son, but instead has his ashes at home.

"He's here," she said. "With me."