They came to Alchemy Farm to mourn.

But there were no formal eulogies. The microphone was used only by the musicians. It was an extreme case of no one knew what to say.

The young people — most of them still in high school — could only try to support each other in their grief.

They had gathered last week for a memorial service for Sean Stigberg-Mellman, a resident of Falmouth since he was 4 years old. Dead at the age of 19 from a heroin overdose.

If anything, the many adults in attendance could only ask questions, especially, "What can we do to protect other children?"

That was a difficult one because Kathleen Stigberg, one of Sean's mothers, worked at Gosnold on Cape Cod, the Cape's largest addiction treatment organization, for five years in admissions and as a case manager. She's also been in recovery for 30 years from alcoholism.

She knew the warning signs and what to do about them.

Also, Sean was a responsible young man, who excelled in athletics, and wasn't a big risk-taker. Polite, helpful, is how adults described him. He did well at Upper Cape Cod Regional Technical School until senior year when his life began to unravel.

"You ask him to do something, and he always did it," said Patricia Mellman, his other mother.

"You could give him a long leash because he was so responsible," Stigberg said.

So when Sean started trying drugs, it didn't seem like a big deal.

He started smoking marijuana at about 12, said his childhood friend, Silas Larkin, 18, of Falmouth. They both did, Larkin added.

"I didn't think what we did together would lead to shooting up," Larkin said.

Sean's mothers knew about the pot. Stigberg knew how serious drug use is at that age.

If he wanted to get a driver's license, she told him, he couldn't be smoking pot. She started to drug test him, she said.

That's why she's pretty sure when he got his license at 17, he wasn't smoking pot, much less shooting heroin, she said.

When he was 18, however, Mellman, who lives just minutes from Stigberg in East Falmouth, made a shocking discovery.

Sean had moved in with Mellman for his senior year, after living much of his life at Stigberg's house. The women had broken up after adopting Sean and Zachary, who is younger by just a few months, as infants. Sean's biological parents battled addiction, Mellman said. Although the women separated years ago, they always lived near each other to raise the children.

One morning in February 2013, Mellman was driving Sean to school and he could barely keep his eyes open. He leaned out of the car and vomited. And then Mellman noticed his arm.

There was a single needle mark.

"I drove him to school saying 'Dope is for dopes. Dope is for dopes,'" Mellman recalled.

At home, it didn't take her long to find a burnt spoon by his bedside.

The next night Stigberg confronted Sean.

"'I know you're doing something more serious, and I don't even need to know what it is,'" Stigberg told him. "'But you need help.'"

"He just broke down and cried and said he was trying to stop on his own," Stigberg recalled.