The expanding exchange of people, ideas and money is a result of policy changes over the past few years in Washington and Havana that have opened up travel and giving for Cubans and Cuban-Americans. After decades of being cut off by politics, the airport here is always crammed with Cuban-Americans coming to see family and lugging in gifts, just as it is now more common to see Cuban artists, academics and dissidents in Florida or New York, often mingling with the established Cuban-American elite.

“The broad trend is Cubans’, regardless of their politics or ideology, coming here to visit, live and work, and go back and forth,” said Julia E. Sweig, the director for Latin American studies at the Council on Foreign Relations. “It’s an organic dynamic in which the elite are participating.”

For many families, the transition from keeping Cuba at a distance to pulling it close has taken time and multigenerational discussion. When Kevin O’Brien and some of his cousins decided a few years ago to take charge of the long-dormant Bacardi Family Foundation, they agreed to focus much of their support on Cuba, returning to a version of an old family custom: Relatives pool money together and distribute it to a chosen cause or person.

Not everyone gives; there are about 500 Bacardis now, and disagreements over the homeland are common, said Mr. O’Brien, the foundation’s president. But since reactivating the foundation in 2012, the Bacardis have raised $28,000 for water filters after Hurricane Sandy and financed efforts to encourage creative expression, with art, photography and music.

Cuban officials seem tolerant, to a point. Eager to improve their weak economy, they welcome the money but fear its power, said one artist supported by the foundation who spoke on the condition of anonymity to avoid reprisals. He added that while Cuba’s leaders had become more welcoming — no longer calling exiles gusanos, or worms — they were still distrustful, determined to keep Cuban-American influence from becoming an immediate challenge to the state.

For now, experts say that seems unlikely. The organized money going to Cuba, beyond an estimated $2.6 billion in family remittances, mostly from the United States, remains relatively small. A lot of it is still funneled into the Catholic Church, one of the few institutions allowed to play a role in civil society. The Order of Malta provided 800,000 meals for the elderly in Cuba last year with around $250,000 in donations, mostly from Cuban-Americans in Miami. The Cuban police nonetheless interrogated some of the old women being fed.