But eagle-eyed fans have now spotted a rather hilarious detail in the birthday photo – Elton's apparent obsession with Marmite!
Taking to Instagram on Thursday, he gave fans a sneak peek of his children's playroom as he posed with his cake – which was of numbers shaped into a seven and a four, and decorated with blueberries and raspberries.
WATCH: Elton John and his children get festive in stunning home
In the background of the snap were his two sons and a stack of what appeared to be several varieties of Marmite.
Fans soon shared their amusement over Elton's love of the controversial food spread, with one writing on Twitter: "Could Elton John have any more Marmite jars? No, no, he couldn’t it seems."
A second joked: "Elton John and The Seven Marmites – a new film coming to a cinema nowhere near you. @marmite #EltonJohn." A third added: "Elton John has a tremendous amount of Marmite and I’m a big fan."
Elton accidentally revealed his love of Marmite
The official Marmite Twitter account even got in on the action, posting: "Happy Birthday to Marmite lover Sir Elton John."
Elton looked like he was having the best time on his birthday, captioning his photo: "Having the best birthday ever with my 3 wonderful boys. What could be better??"
In the picture, his two sons could be seen behind him playing next to a counter full of Star Wars toys. Underneath the counter, lots of clear plastic boxes could be seen, no doubt neatly filled with more toys and games.
Elton has several varieties of Marmite
The large family room is the perfect space for Elton and David Furnish's two boys, Zachary, ten, and Elijah, eight.
Several fun pictures take pride of place on the four walls, including a red rocket, an orange basketball and a colourful trainer. The back of the room is made out of shelves filled with books and Marvel superheroes.
Other accessories that feature in the room include a mini sofa, which was no doubt bought for the boys when they were younger, and a large rug, where they most likely play together after school.
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