Friendly exes, indeed.
Arnold Schwarzenegger turned 68 years old on Thursday, and was spotted celebrating with his ex-wife, Maria Shriver, in Beverly Hills, California. The amicable pair had lunch at the Montage Hotel with their two daughters, 25-year-old Katherine and 23-year-old Christina.
WATCH: Arnold Schwarzenegger Calls Couples Therapy With Maria Shriver the 'Biggest Mistake' He's Ever Made
Maria filed for divorce from Arnold in July 2011, though their divorce has never been finalized. The two split after it was revealed he fathered a son more than 14 years earlier with an employee in their household, Mildred Baena. Arnold has since moved on with physical therapist Heather Milligan.
In an interview with Howard Stern on his Sirius XM show last month, the Terminator Genisys star called his and Maria's split "without a doubt the biggest setback and the biggest failure" in his life. He also took full responsibility.
"Not only failure, but you really feel like, 'I'm to blame for it. It was me that screwed up,' and you can't point the finger at anyone else," he said candidly.
Still, he stressed that he and Maria -- who he still referred to as his wife -- and their four children have a great relationship. "My kids are a straight 10," he gushed. "I am so proud of them and I'm so in love with them. I love my kids so much."
Patrick Schwarzenegger, 21, obviously returns the sentiment. He Instagrammed a sweet shout-out to his famous father on Thursday, writing, "68 and you're still bigger than me! When will you let me catch up?!? Happy birthday pops."
Arnold's close pal, Magic Mike XXL star Joe Manganiello, also took a moment to wish him a happy birthday, Instagramming this cute picture of the buff pair showing of their goofy sides.
"Happy Birthday to my friend @Schwarzenegger! Here's to many more great adventures!" Joe wrote.
The former governor of California took some time out to show his fans he appreciated all the birthday love on his special day.
"I want to thank everyone for all the birthday wishes," he said in a Twitter video. " ... I'm having the greatest time. My 68th birthday, wow, I'm in the gym working out ... and now I'm going to have a little bit of lunch with my family, so hasta la vista, and have a great time, OK?"
NEWS: Arnold Schwarzenegger Writes Heartwarming Handwritten Letter to Ailing Fan
ET caught up with Arnold last month, when he shared his Hollywood advice to his son Patrick. Watch below!