The Pulp Fiction star uploaded a surprising video to wish rapper, Pitbull, a happy birthday on Friday.
In the clip, John said: "This is a message to Mr World Wide, Armando Perez, Pitbull. Chico, I just can't tell you how much it means to be in your life. Happy birthday.
VIDEO: John Travolta and daughter Ella dance in memory of Kelly Preston
"Love to share with the world your schools' message to you for your birthday so slide to the right and look at this, you won't believe it."
The video John is referring to is a compilation of birthday wishes from pupils at Pitbull's charter schools – SLAM! Sports and Leadership Management – in Miami, Florida, and Henderson, Nevada.
John shared a touching birthday tribute to friend Pitbull
Fans were touched by the sweet birthday shout-out from John, with one writing: "Love you, John! You are a beautiful human being!"
A second added: "Happy Birthday!! @pitbull Love what you did John! Cool!!!" A third gushed: "You are a sweet man." While a fourth added: "I love you, John. Amazing tribute."
John had been keeping a low profile on social media since the start of the year, but delighted fans with an upbeat Instagram post this week.
John tragically lost wife Kelly Preston in July
The Grease star took to social media on Wednesday to reveal his excitement at finding out his Capital One advert, in which he starred alongside Samuel L. Jackson, had been ranked as one of the most likeable in a new article.
Alongside the post, which was also accompanied by a picture of John and Samuel, the Hollywood star wrote: "Congratulations Sam! We were ranked the most liked stand out commercial of the year!"
The happy post was particularly nice for fans to see, following John's difficult year. The Saturday Night Fever star tragically lost his beloved wife Kelly Preston to cancer in July, and marked his first Christmas without her in December.
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