Elton and David have been together for more than 20 years and the wedding was held exactly nine years after they entered into a civil partnership.
Both Elton and David documented their big day with a series of photos on Instagram, which they posted with the hashtag: #sharethelove.
One of the pictures showed Zachary looking in a mirror as his dads get him ready for the ceremony - although he appears to be more interested in his Lego than his suit!
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