AceShowbiz -

After managing to keep her pregnancy a secret from the public for nine months, Anna Kournikova allegedly gave birth to twins on Saturday, December 16. And now, it has been reported that Anna, together with her boyfriend as well as the father of the twins, Enrique Iglesias, is busy renovating their Miami home to ensure total privacy for the family.

According to TMZ, Anna and Enrique would spend around $600,000 to upgrade their 20,000-square-foot home. The outlet added that they have started the project since the end of summer, during the former professional tennis player's second trimester.

The project included building a 16-foot-tall wall around the home as well as adding a two-story single family house to their property. The new parents were also making sure that everything was safe for their babies, Nicholas and Lucy, by creating a "child barrier for pools."

It came as no surprise that the couple would be willing to spend that much of money to upgrade their home, considering that they went into hiding to make sure that public didn't know about Anna's pregnancy. "A friend told me like five months ago [that] they were pregnant but keeping it very, very undercover," a source told PEOPLE. "They basically hang out with family and very close friends. They mostly keep to themselves."

Enrique and Anna started dating back in 2011 after the Russian beauty played Enrique's love interest in his music video for "Escape". The couple might barely speak up about their relationship, but Anna once told Women Health in the same year that having children was definitely on her agenda, yet marriage was not a priority.

"I absolutely want to have children, whether I have my own or adopt. I love taking care of people," she told the mag. "[Marriage] isn't important to me. I'm in a happy relationship -- that's all that matters. I believe in commitment. I believe in being open and trusting each other and respecting each other completely."