Almost two decades ago, while on bed rest during her first pregnancy, writer Lizette Lantigua penned a picture book about a young boy who flees Cuba. As a journalist interviewing balseros arriving from the Communist island, she wanted the stories of these courageous rafters to reach an audience beyond South Florida.

But it took her several rewrites, a contest and the decision to expand to the longer format of a novel for the story of Luisito Ramirez Jemot to be published this summer. And just as Lantigua kept a promise to herself, the hero of Mission Libertad spends more than 200 pages trying to keep true to a vow he made to his grandmother — all while battling spies, entertaining his first romance, discovering his Catholic faith and adjusting to life in Maryland.

“I grew up in Hialeah surrounded by all these stories people told about their experiences leaving Cuba and coming here,” says Lantigua, 46, born in Queens to Cuban parents. “Then as a journalist I interviewed many Cubans arriving by rafts, including one who had windsurfed here.”

The stories became the foundation for the fictional tale. In Mission Libertad you learn about the storming of the Peruvian Embassy in Cuba in 1980 and the Mariel Boatlift that followed, which sent more than 125,000 Cubans to the United States in boats, yachts and ships. You learn, too, about La Virgen de la Caridad, Cuba’s patron saint, and the shrine that houses her statue in Miami

Beyond the history lessons, Lantigua also threads her tale with real-life situations that typify the exile experience: Luisito’s first time at a grocery store. Luisito astounded by kids playing with a pet rock, an American novelty item at the time. Luisito trying out for the school basketball team.

“What I had most fun writing about was how my main character, Luisito, integrates into American life,” she says. “I think it’s the kind of experience readers can identify with.”

Mission Libertad has a strong Catholic motif, as Luisito fulfills a secret religious mission entrusted to him by his grandmother. During a conversation with his cousin Tommy, Luisito talks about praying during his harrowing raft trip from Cuba. Tommy assures him that God must’ve listened. Lantigua writes: “Luisito hadn’t really thought about that. God did hear him. The thought gave him peace.”

That recurring theme of a how the 14-year-old develops his faith after coming from an atheist country proved attractive to Mission Libertad’s publisher, Teen Pauline, a new imprint of the publishing house of the Daughters of St. Paul. The Catholic publisher had wanted to branch out to middle grade fiction and had been advertising for manuscripts through a contest when Lantigua sent a draft to its Boston office.

The manuscript, however, was too long and needed more tweaking, the editors told Lantigua. She submitted a new version a year later and this time, the editors wanted to publish it. They were especially taken by the historical backdrop and the story of a teen’s growing in faith.

“Luisito is likeable,” says Jaymie Stuart Wolfe, children’s editor at Pauline Books and Media , “and his story feels real. It rings true.”

Teen Pauline has high hopes for Mission Libertad. “We’d love to see every kid in Catholic school read the book. But we think any student can take something from it. This is a story about the price you pay for what you believe in,” Wolfe says.