After graduating from Bowdoin College in French and art history, and spending two years with film production companies in New York City, Codina returned to her Cuban-American roots, working for the Miami International Film Festival.
The idea for the film began just before the 2005 wedding.
"Everyone was very happy for Monica when she found David, but there seemed to be an unspoken feeling that this was a cute gesture between two kids rather than a serious adult commitment," said Codina.
"There was a complete understanding that they were very much in love, but the full transition to see them as adults hadn't happened yet," she said. "That motivated me to start the project, seeing Monica and David not just as adults with intellectual disabilities, but as people, individuals and as adults."
The film opens just as the two prepare for their lavish, storybook wedding.
"It's all about him, and all about me," says Monica. "This is my day. It's my life, to be with my husband forever."
While Monica, then 33, and David, then 27, are capable beyond expectations, their parents have trouble letting go.
"As parents, we want people to look upon our children with special needs like anyone else," says Maria Elena. "We want them to be treated with respect and with dignity and to not stare at them and whatever. And yet, because we want to protect them so much, we are typically the first ones who treat them poorly by subconsciously denying them their rights to have a normal life."
As daily life unfolds, Monica's mother manages the couple's lives, teaching them to cook and even walking in to the bedroom to wake them each morning. Their routine is disrupted by a move to a bigger home and David is diagnosed with diabetes.
At an emotionally-charged point in the film, Monica writes a letter to her biological father, upset over his absence in her life.
"Those who were close to her knew that of course she was fully aware of the fact that he had left," she said. "But they wondered what she truly felt. It was an incredible moment to hear her express what she might be feeling. And she tells us exactly."
Monica and David are physically demonstrative, but the director keeps their private life private.
"They are perfectly capable of having sex," said Codina. "And the desire is certainly there. But I don't feel it's my place to divulge their relationship, and they didn't want to share it with the world."
The couple talks about having children and their parents do not overtly forbid it.
In the past, sexuality was not considered an issue because of the inaccurate belief that what was then called mental retardation left people with Down syndrome in permanent childhood, according to the NDSS.
But today, doctors know that children with Down syndrome develop much the same way as their peers, and have all the same sexual feelings and needs for intimacy.
Experts recommend sex education -- learning about reproductive health, birth control and sexually transmitted diseases.-- as the the best way to plan for this aspect of adulthood.
Monica's mother addresses the issue of parenthood in the film: "Obviously people with developmental disabilities have needs and desires. They are very much like everyone else. And so I think parents need to be as aware of the contraception needs of a person with an intellectual disability as to the needs of their other children"