Relatives of Jean Marie Stewart, a Brookline girl who vanished exactly 28 years ago at age 16 in Florida, plan to hold a funeral service today on the anniversary of her disappearance -- or, her brother says, of her murder.

Prompting the service is the fact that in November, authorities positively identified skeletal remains found in Hialeah, Fla., in April 1981 as Jean.

"We're getting closure on this, and they started the investigation. We're just thankful that this is coming to an end," Jean's brother, Eric Stewart, said yesterday.

Police in Hialeah confirmed they have opened a homicide investigation, which is active, according to Sgt. Ralph Nazario.

"We're at that juncture still where we're not at liberty to disclose anything about the case. We want to protect the integrity of the case. We're moving along. We're investigating it as an open homicide, and that's where we're at," Sgt. Nazario said.

The service is scheduled for this morning at St. Bernard Church in Mt. Lebanon, where Jean's father, Robert E. Stewart, lives.

As of yesterday, family members were still working out the details of the service, including who would eulogize Jean.

In 1978, Jean was granted permission by her father to move to Florida with her boyfriend's family.

On March 25, 1980, Jean went to a going-away party and drove home with her boyfriend, David Nolle. They stopped at a convenience store in Miami Lakes, Fla.

Mr. Nolle's sister has said in an interview that her brother went inside the store and when he returned, Jean was gone and was never heard from again.

Pittsburgh police got involved in the case and sent Jean's dental records to Florida authorities.

However, it wasn't until last year that a volunteer with a Web-based network which tries to find missing persons and identify remains helped put a name to the skeleton found in Hialeah, next to Miami Lakes, just 13 months after Jean vanished.

A positive match was made with dental records. Authorities have not been able to explain why the match took 27 years.

As the investigation grinds along, Mr. Stewart holds out hope that the person responsible for killing his sister will be arrested.

"I think justice will prevail," he said.