On Wednesday, Lauren was pictured arriving at Nice airport, her burgeoning tummy on display in a tight black tank top teamed with fitted white jeans. It is thought that the New York socialite is around 12 weeks pregnant with Simon's first child.
According to reports, X Factor mogul Simon is set to return to the south of France on Wednesday evening to spend time with mum-of-one Lauren.
Rather than return to his luxury slipstream yacht, moored nearby, the couple will hole up in a rented villa together. And judging by the amount of luggage Lauren arrived with, she will be staying for more than a couple of days.
"At her stage of pregnancy, it's little wonder she may want to be on dry land instead of sea," a source told the Mirror.
Lauren's visit comes after her divorce from husband of ten years Andrew Silverman was settled in New York last week.
Her property mogul husband filed for divorce shortly after news broke of his wife's infidelity with his friend.
The deal was reached in Manhattan last Wednesday, with Lauren said to have won half of her $4 million pre-nuptial agreement.
The 36-year-old and Andrew are said to have come to an agreement to share custody of their seven-year-old Adam. And, according to TMZ, Lauren, who is due to give birth in February, will live in New York to be close to her son.
The couple wanted to reach a settlement as quickly as possible. Property millionaire Andrew told TMZ, "As I've said all along, my priority was resolving this quickly for the sake of our son.
"Lauren and I both love him very much and I'm looking forward to starting a new chapter in our lives."
Simon, meanwhile, has spoken for the first time about becoming a father.
On the red carpet at the One Direction movie premiere in London on Tuesday, the 53-year-old told Magic FM that he's "ready, excited and very happy" about the baby, calling Lauren " a lovely girl".
He went on to tell the BBC that he was "proud", adding, "Things are changing in my life right now, for the better.
"I'm proud to be a dad… It's something I hadn't thought of before, but now I know I feel good about it." The star added, "She's a very special girl."
It will be the first time that Lauren has seen Simon since news of her pregnancy broke at the end of last month. They remained in close contact, however, over the past few weeks while she retreated into her $4 million rental home in the Hamptons.
A source who is close to Lauren and part of her social circle on the Upper East Side of Manhattan, told the Mail, "Lauren is so excited, It will be the first time she has seen Simon in weeks, she really loves him and they can't wait to be together."