The 53-year-old actor posted a super sweet message in celebration of Caitlin McHugh's birthday.
John Stamos is pretty smitten with girlfriend Caitlin McHugh.
In celebration of the actress' 31st birthday over the weekend, the two spent the day at Disneyland in Anaheim, California, and brought along Stamos' Fuller House co-stars, Bob Saget and Dave Coulier, as well as his former Grandfathered co-star, Josh Peck.
Gushing over his girlfriend, the 53-year-old actor posted a photo of himself dressed as Tigger while kissing McHugh, who was wearing a Winnie the Pooh costume. "Any day spent with you is my favorite day," he captioned the pic. "So, today is my new favorite day. Happy Birthday Babe!"
Further flaunting their love, McHugh -- who's been dating Stamos for over a year -- shared the same photo, writing: "'How do you spell love?' said Piglet. 'You don't spell it--you feel it,' responded Pooh. #grateful #birthdaygirl."
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Meanwhile, the rest of the guys appeared to have a great time at the theme park. "Best day ever is getting to spend the day @disneyland with these three funny gents. @bobsaget @johnstamos @shuapeck #disneyland," Coulier, 57, posted on Instagram.
Saget also shared a selfie of him posing with his Fuller House co-stars, noting that his girlfriend and Coulier's wife, Melissa Bring, were with them. "My brothers and me @Disneyland havin' the time of our lives with our ladies. FH in the DL," the 60-year-old actor wrote.
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In March, Stamos revealed to ET what his Fuller House family really thinks of McHugh. "They all love her more than me. They're like, 'Is Caitlin coming?'" he quipped. "'We don't care about you, is Caitlin coming?'"
Stamos added that his girlfriend is "just a good person," and the feeling seems to be mutual. “I'm very happy, he's super supportive, and I really couldn't ask for anything better,” McHugh told ET in January, praising her boyfriend. “He's very encouraging of anything I want to do career-wise. I really appreciate it a lot. You don't get that with every guy.”