The 37-year-old New Yorker, who is now seven months pregnant, welcomed friends and family to the Los Angeles mansion, where they were greeted at the door by the sight of a beautiful Christmas tree and a handsome man serving drinks.
X Factor mogul Simon had already excused himself from the event. Before guests began to arrive, he was seen driving off in his $1.7million Bugatti for a meeting at the Peninsula Hotel.
Simon and Lauren will be jetting away to the Caribbean together for the Christmas holidays. And, according to reports, they might have even more to celebrate this festive season.
Now that Lauren has finalised her divorce from her husband Andrew Silverman, Simon is reportedly planning to propose before the baby’s February due date.
"Simon doesn't want Lauren to give birth to his son as a single mum," a source told People. "He is ready to commit."
Lauren is already a mum to a seven-year-old son from her previous marriage; this will be Simon’s first time as a dad.