At Casa Viva, a rehab center in Rio that takes in children, sobbing and playful laughter both echo off the walls. The home takes on children addicted to crack, who lived on the streets like zombies among the trash.
Rio city officials have tallied almost 700 children and adolescents living on the streets who are hooked on alcohol or drugs. Though crack devastated many inner-cities around the world decades ago, it is just starting to do major damage in Brazil.
Authorities said that of all the addicted street kids, some 10-15 percent are now dependent on crack, a cheap cocaine derivative.
"They take crack because it is a less expensive drug, and one they get hold of easily. But the worst thing is that it gets them addicted faster than other drugs, and causes serious neurological damage," Monica Blum, a social worker, told AFP.
At Casa Viva, there are a dozen kids aged 10-14 who are inpatients, being cared for by a team of specially trained doctors, psychologists and addiction counselors.
Tossed out on the tile floor, one of the kids undergoing detox treatment is crying and sobbing: "I want to go home."
But, as he then told a reporter, his "home" is actually the street, to which he ran away about four years earlier to get away from his mother's fearsome physical abuse at home.
Matheus, Josephi and Adrieli are three teenagers proud they have been able to make progress at the home, where they eagerly take part in program activities.
"I was so wasted before coming here that at home, I beat up my grandmother. But then I told her 'I need help'. And she brought me here. When I got here I weighed 23 kilos (51 pounds), but I am doing better now," said Adrieli, 14.
She followed her addict mother into the drug world at the age of 9, Adrieli said.
While they are in treatment, Matheus and Josephi pass the time playing soccer and singing.
Due to neurological damage, crack addicts often have unusual behavior that can become violent.
The signs are easy to spot among kids who come to Casa Viva from hillside slums like Jacarezinho, on Rio's north end. Last week alone, 38 adults and 15 kids from the neighborhood were taken to drug treatment centers.
Addiction treatment capacity is phenomenally below need: in a city of seven million there are three treatment centers and 150 beds for inpatients.
Under a new law, authorities can force minors to undergo treatment. But adults have to agree to it. And in most cases, they are unwilling.
"If they have a really high level of dependency, they suffer relapses," said another social worker, Daphne Braga, as she walked toward an area nicknamed Crackland, where slum residents often gather to get high.
Some, still wasted and glassy-eyed, march mechanically to a bus stop to head across town.
Others want to stay put where their crack is. Like Rosangela who sleeps on a cardboard box on the sidewalk.
"I am not leaving," she screams. "And you cannot make me go," she says claiming she has been hurt in an earlier effort to move her.
The surge in Brazil's crack consumption -- there are no official statistics -- drove ex-president Luiz Inacio Lula da Silva to launch rehab programs for young people.
And many kids like Adrieli are grateful that they have seen light at the end of the tunnel.
"I want to be a judge, or a lawyer, so that my grandma will be proud of me," she smiles, her eye on a different path in life.