The lovebirds—who are expecting their first child together—were spotted kissing and cuddling on a sun lounger by the beach in the South of France, where they apparently had no problem showing off their affection for each other.
Earlier in the day, Silverman was spotted out showing off her growing baby bump, strolling on the streets solo while flashing a giant smile.
The parents-to-be have been vacationing together in St. Tropez, enjoying a romantic getaway for the first time since Silverman announced her pregnancy. They've been photographed sharing a sweet peck and walking hand-in-hand over the past few days.
"They are definitely a couple," the source said. "The relationship is loving and they're very happy together."
Cowell also recently broke his silence about becoming a dad, telling the BBC, "Things are changing in my life right now, for the better."
"I'm proud to be a dad. It's something I haven't thought of before, and then, now I know I feel good about it. And she [Silverman] is a very special girl."
Looks like it!