Zoe Saldana celebrates twins' birthday: 'Three years ago our lives changed'

Nov. 28 (UPI) -- Zoe Saldana was feeling reflective on her twins' third birthday.

The 39-year-old actress dedicated a heartfelt message to Bowie and Cy, her elder sons with husband Marco Perego, while celebrating the occasion Monday.

"Happy Birthday Bowie and Cy!" Saldana wrote on Instagram. "Today, November 27th will always be the happiest and scariest day of our lives. On a day like today, three years ago our lives changed forever. We went from being two to four in just 2 minutes."

"Your strength, determination, curiosity and kindness humble us every day," she added. "Thank You for choosing us to guide you through the first stages of your purposeful path in life. You are both meant for greatness and by the grace of God your father and I will make sure you grow up to be exceptional men."

Saldana and Perego, who married in June 2013, are also parents to 9-month-old son Zen. The actress said in an interview with E! News in March following Zen's birth that she doesn't plan to have more children.

"I think we're done," she shared. "I'm the only girl and it's OK. I'm enjoying being in a house full of men; I grew up in a house full of women, so I feel that either the universe is being ironic with me or it's being absolutely purposeful, and I'm accepting the challenge."

"I love raising boys," the star added. "There's so much that I'm learning about men by seeing them in their early stages in life. Our kids are wonderful. They're happy!"

Saldana is known for playing Gamora in the Guardians of the Galaxy films, and will reprise the role in Avengers: Infinity War. The new movie will release a first trailer Wednesday.