On Sunday, as President Obama's plane touches down in Havana, Cuban-Americans will be watching. Many of them have endured periods of separation from their families since the early 1960s.

Award-winning author Margarita Engle is one of those people. She is the first Latina to win the prestigious Newbery Honor for her 2008 book, The Surrender Tree: Poems of Cuba's Struggle For Freedom. She is also the author of Enchanted Air, Two Cultures, Two Wings: A Memoir, a 2015 autobiographical book of narrative poetry.

It tells her story of growing up in Los Angeles before getting to know her family in Cuba as a child and teenager in the late 1940s and '50s, and then being separated from that extended family in the ensuing 40-plus years.

One poem tells about a time when her family had been questioned by the FBI for receiving letters and phone calls from her grandmother in Cuba.

On Friday, she stood at a podium at the Library of Congress, receiving a Walter honor award for Enchanted Air. A few days prior, President Obama had reinstated regular mail service in the latest sign of improved relations. As she spoke to the packed ornate room, her voice quavered with emotion.

I wrote Enchanted Air, Two Cultures, Two Wings, at a time when there was no public glimmer of hope for renewed relations between my parents' homelands, Cuba and the U.S. I wrote it believing that no American president would have the courage to make peace with Cuba, and that peace would have to wait until a future generation, after today's children grew up and one of them became president.During the same week when advanced review copies arrived on my doorstep, President Obama announced a thaw in Cold War hostilities, proving me wrong. My childhood memories, written as a plea for peace and reconciliation, were suddenly transformed into a song of gratitude.

Enchanted Air ends with a poem as question that made the timing of the award so poignant:

All I know about the futureis that it will be beautiful. An almost-warcan't lastforever. Someday, surely I'll be freeto return to the island of all my childhood dreams. Normal diplomatic relations. An ordinary family— united. Magical travel, back and forth.It will happen. When?

The Walter award is given in recognition of the life of novelist Walter Dean Myers. It is sponsored by the group We Need More Diverse Books.

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