By baby teeth chart
March 31, 2015
Miracle twin boys Alexandre and Ronaldo first birthday

Baby's first birthday is always a cause for celebration, but the milestone is especially sweet for Linda DaSilva. It was a little over a year ago that the New England mom went into labor with her twins at just 24 weeks.

She was rushed to Tufts Medical Center in Boston, where after three (!) pushes, she delivered son Alexandre. The very premature babe weighed a tiny 1 pound, 10 ounces. But instead of delivering the second baby, DaSilva's labor suddenly stopped.

Rather than force things, doctors decided to let the baby stay put until labor started back up again. That procedure, called delayed interval delivery, is risky, but the medical team knew that the twin's chances of survival would only improve the longer he stayed in utero. So DaSilva waited nearly a month—24 days, to be precise—until her second son was ready to be born.

Against all odds, the delivery went off without a hitch and baby Ronaldo was even a full pound heavier than his brother. "It's really a one in a million thing," said Jonathan Davis, M.D., the hospital's chief of neonatal medicine, of the large gap between the births. "I don't know if it's ever been done this long."

No word on how long the boys were kept in the NICU, but now, a year later, they are the very picture of good health. The adorable kiddos even went back to Tufts Medical Center to ring in their first birthday with the doctors and nurses who cared for them. "They're so beautiful, they're happy, they're healthy," DaSilva said. "I have everything I need here."

Happy first birthday, Alexandre and Ronaldo!

Bonnie Gibbs Vengrow is a New York City-based writer and editor who traded in her Blackberry and Metro card for playdates and PB&J sandwiches—and the once-in-a-lifetime chance to watch her feisty, funny son grow up.Follow her on Twitter, Pinterest, and Google+

Screenshot of Alexandre and Ronaldo celebrating their first birthday from the ABC News video above