The on-screen couple guested on The Tonight Show with Jimmy Fallon, serenading and flattering each other.

A very pregnant Drew Barrymore showed up with Adam Sandler on The Tonight Show. Drew told host Jimmy Fallon, "Every 10 years, we get to fall in love again." Adam continued, "We really do. We enjoy it. We have a lot of fun together."

The two then started singing their feelings for each other, prompted by host turned guitarist, Jimmy. Drew started off, saying she promises to love the 47 year old-actor every 10 years. Adam responded, "I'll always be true, even as we get older."

The song continued until Adam ultimately asked the pregnant actress how he compared to Hugh Grant and then Ben Stiller - both also teamed up with Drew on-screen. The actress remarked that Adam was the better on-screen lover.

Adam also sang about how he'd love the actress her boobs touch the floor, after Drew swore to still love him 'til 64. 

According to E! Online, the on-screen couple is glazing theaters once again with their third team up on the big screen.

The upcoming movie, entitled Blended, stars the A-couple and is reportedly a story about two single parents who went out on a first date but unfortunately did not click, says E! Online. Trapped in the same vacation resort with their kids, the two single parents soon found themselves attracted to each other, adds The Hollywood Reporter.

The movie is produced by Mike Karz and co-produced by Sandler's Happy Madison, notes The Hollywood Reporter, while Frank Coraci directed the upcoming romantic comedy flick.

The Adam Sandler and Drew Barrymore-pairing has been notorious at the box office, leaving impressive sales with their past chick flicks. According to E! Online, the stars' first pairing, 1998 movie The Wedding Singer had $123 million gross sales while their second pairing, the 2004 movie 50 First Dates, went up to $198 million in sales.

Blended is expected to hit theaters May 23 in the US. Until then, fans of the couple can enjoy the movie's official trailer and a clip of the the Every 10 Years song in the videos below.