Katy Perry chimed in on ex-boyfriend John Mayer's Instagram for the sweetest reason. The pop star wished John's dad a happy 90th birthday when he posted a cute father-son pic for the milestone occasion. But, John dropped a heartfelt message of his own with a special reference for eagle-eyed fans. » SUBSCRIBE: bit.ly/AHSub » Visit Our Website: www.AccessHollywood.com/ Get More Access Hollywood: Facebook: www.facebook.com/AccessHollywood Twitter: twitter.com/accesshollywood Instagram: instagram.com/accesshollywood Snapchat: OfficialAccess About Access Hollywood: "Access Hollywood" is a nationally syndicated daily entertainment news show. "Access Hollywood" delivers the most comprehensive coverage of entertainment news and personalities on television, featuring in-depth celebrity interviews and behind-the-scenes accounts of the most important events in Hollywood. Katy Perry Wishes John Mayer's Dad A Happy 90th Birthday: 'Looking Fantastic As Ever' In Hollywood | Access Hollywood Access Hollywood www.youtube.com/user/AccessHollywood