By CAROL MARBIN MILLER

Do siblings have a basic right to be raised together in the same family?

That thorny question, now confronting a Miami judge who will decide whether to return a 4-year-old girl to her father in Cuba, may determine whether an already tense, complex and emotional court battle will become even more complicated.

Alan Mishael, a Miami attorney who represents the 12-year-old half brother of the girl at the center of the international custody dispute, has asked that the boy and his adoptive parents be allowed to call and cross-examine witnesses at an upcoming trial into the fitness of the girl's birth father, a farmer and fisherman from Cuba.

''Children have a constitutional right to remain with their siblings, unless the state presents a compelling reason for splitting them up,'' Mishael said.

At the end of a nearly four-hour hearing Tuesday afternoon, Miami-Dade Circuit Judge Jeri B. Cohen declined to rule on the request, saying she needed more time to study what state law allows.

She gave several hints, however.

Cohen long has been a devotee of ''therapeutic jurisprudence,'' a movement that encourages judges and lawyers to use the law to improve the well-being of people -- including emotional welfare. From that perspective, Cohen said, she was inclined to give the preteen boy ''a voice'' in the proceedings.

''From a therapeutic standpoint, it's the right thing to do,'' Cohen said. ``But that doesn't mean it's legal.''

IMPLICATIONS

Granting Mishael's request for the boy to have the right to be a full party to the dispute could have significant implications. Depending on how the judge frames his participation, Mishael could be given the right to call and cross-examine witnesses, take depositions and object during trial.

Granting foster children a ''right'' to live with their siblings could prove a nearly impossible task to fulfill for Florida child welfare administrators.

Though a Department of Children & Families spokesman said Tuesday the agency did not have recent data readily available on the percentage of siblings in state care who are separated, figures from the past decade show DCF has had enormous difficulty keeping brothers and sisters together when they enter state care.

A 2000 internal audit, for example, found that no DCF local district had succeeded in placing more than 60 percent of sibling groups in the same home. Several districts had succeeded in no greater than 45 percent of cases, and one had succeeded in only 14 percent of cases. Miami-Dade's success rate was 52 percent.

A 2001 audit found that, statewide, siblings in state care who were eligible for adoption were in the same home 67 percent of the time; in Miami-Dade the success rate was 43 percent.

And a soon-to-be released report from the University of Chicago found that siblings in foster care often do not live together in the same home, and visitation among brothers and sisters ''is occurring infrequently'' in Miami-Dade and Monroe, and ''not occurring regularly'' in Broward. The report says brothers and sisters don't get opportunities to talk on the phone or communicate in other ways.

Mishael argued that his client's right to be close to his sister is on par with the girl's father's right to raise her. The father's ''assertion of a fundamental right is on a collision course with the right of the brother to keep the girl where she is,'' he said.

Ira Kurzban, who represents the birth father, said DCF attorneys have failed as yet to show that the father was anything but loving and supportive of his daughter before she left Cuba in December 2004 with her mother for the United States. Absent such evidence, he said, the father's rights to raise his daughter trump the rights of others.

LOVED, WELL-CARED

''All evidence in the depositions was that [the girl] was in a loving relationship not only with her parents, but among the larger family as well,'' Kurzban said. ''She was loved and well-cared for in Cuba . . . The evidence is that my client had a good, loving, close relationship'' with his daughter.

And because her 12-year-old brother was adopted last summer by the children's foster parents, Kurzban said, the boy no longer has the same legal rights, under Florida law, as other siblings. State law, he said, terminates the bonds between siblings when one or more of them are adopted.

''This boy has no standing whatsoever under Florida law to intervene in this case or any other case,'' Kurzban said. ``That any harm would come to him is absolutely irrelevant to these proceedings.''