After months of uncertainty, the way has been cleared for U.S. families to adopt 12 Haitian children who've been living at a Roman Catholic institution near Pittsburgh since a chaotic airlift that followed the devastating earthquake in January.

The Haitian government had sent a letter formally approving the adoptions, State Department spokeswoman Rosemary Macray said Wednesday, and the children will be matched with U.S. families over the coming weeks.

Unlike some 1,100 other children flown out of Haiti to the U.S. after the quake, the children at the Holy Family Institute in Emsworth, Pa., were not part of the adoption process prior to the disaster and, according to some legal experts, shouldn't have been eligible for the emergency program. Most of them had birth parents still living.

However, Macray said those parents, who were interviewed by U.S. officials, have formally relinquished custody.

Since their arrival in Pittsburgh on Jan. 19, the children — ranging in age from almost 2 to 13 — have been staying at the Holy Family Institute.

Preliminary steps were taken to match the children with adoptive families, and those matches will be reviewed to ensure their viability, said the institute's president, Sister Linda Yankoski. She said the four pairs of siblings among the 12 children would be kept together.

Yankoski said the prospective adoptive families are far-flung — from Oregon, Colorado and Illinois, for example. They are not being identified at this stage, and she said it's possible some of the matches could be changed.

"We have to come up with a thoughtful transition plan for these children," she said, noting that some of the children didn't understand the concept of adoption and had grown used to living with each other.

"We're going to go at the pace of the child," she said. "We're going to follow their cues."

Initially, the Haitian children were kept largely apart from the American children at Holy Family, but this fall the older ones attended public school.

Other highlights of their stay were their first experiences with hot showers and with snow.

"No one had to teach them to make a snowball and throw it — that came naturally," Yankoski said.

She said the children had spoken by phone with their families in Haiti and were expected to remain in contact with them after their adoptions.

"It's been a privilege to be of service to these children," Yankoski said. "We're thrilled that we will be able work with them through this step to having a family they can call their own."

The children were part of an airlift of 54 youths from the Bresma orphanage in Haiti's capital, Port-au-Prince, where two Pittsburgh-area sisters, Jamie and Alison McMutrie, had been volunteering for years. The sisters' urgent post-quake pleas for help were heeded — participants in the Jan. 19 airlift included Pennsylvania Gov. Ed Rendell.