Dax Shepard turns 40 this week, so to celebrate, we're looking back at his cutest moments with Kristen Bell  through the years! Kristen and Dax tied the knot  in a low-key ceremony at a local courthouse last year, and a couple weeks ago, Kristen gave birth to their second daughter , Delta Bell Shepard, who joined her older sister Lincoln. With so many sweet moments throughout the years, take a look at some of the couple's best snaps to celebrate Dax's birthday!
Kristen Bell  attended the Country Music Awards with Dax Shepard in Nashville in June 2013.
Kristen and Dax embraced during a March 2012 day at LA's Griffith Park.
Dax leaned down to kiss Kristen during a day out in LA in September 2008.
Dax Shepard and Kristen Bell  spent an afternoon outside at Bonnaroo in June 2012.
Dax held on to Kristen while they swam in Hawaii in June 2009.
The cute couple took the stage at the June 2012 Guys Choice Awards.
Kristen only had eyes for Dax during a June 2012 event in LA.
Dax helped Kristen apply sunscreen during an August 2008 Malibu beach day.
Dax Shepard and Kristen Bell  cuddled in the crowd at the 2012 CMT Music Awards.
Dax and Kristen locked lips at the 2013 Golden Globes.
The pair went for a boat ride during a September 2009 trip to Sydney.
Dax and Kristen cracked up at the 2012 Do Something Awards.
Kristen grinned from ear to ear while arriving at LAX with Dax in July 2008.
The sweet couple kissed on the red carpet at the 2011 Do Something Awards in LA.
Kristen and Dax had the look of love at the LA premiere of The Hangover Part II in May 2011.
They kept close while cheering on the LA Kings in February 2013.
Dax and Kristen smiled big for the cameras at the 2012 CMT Music Awards in Nashville.
The pair shared the stage at an Apple Store event in NYC in July 2012.
Kristen and Dax laughed while walking around NYC in May 2008.
They couldn't keep their hands off each other at the August 2012 LA premiere of Hit and Run.
Kristen and Dax visited Disney California Adventure Park in April 2008.
They posed side by side at the October 2009 premiere of Couples Retreat in LA.
Kristen and Dax shared a laugh at the Met Gala in May 2012.
They goofed around in the ocean off Maui in June 2009.
Dax and Kristen stopped on the beach in Miami to make out in January 2008.
The couple kissed for the cameras while filming When in Rome in NYC in June 2008.
Kristen cracked up when Dax struck an over-the-shoulder pose at the Film Independent Spirit Awards in March 2014.
Dax and Kristen shared the look of love at the October 2014 premiere of The Judge in LA.
The couple shared the stage at the 2014 CMT Music Awards.
Dax goofed off as he and Kristen left the Oscars in 2014.
Kristen gave Dax a sweet smile at the LA premiere of his movie This Is Where I Leave You.