"Today I lost this amazing woman," he wrote alongside a photo of himself and his mother smiling for the camera. "A wonderful mother and an inspiration to me. Lots of love Wendy.
"So grateful for you and all you have given me and the boys."
"So sorry for [your] loss John, our [hearts] go out to you Kelly and the family," one follower wrote on the post.
"Oh John I am so, so sorry for your loss of such an important person," another added. "Thinking of you and sending love to you and the family."
John has previously shared how his mother was very supportive of him, but didn't mind giving him advice about MAFS and the show's commitment ceremonies.
"The last text Mum sent me was to give me some feedback on some of my advice on MAFS!" he told 9Honey four years ago.
According to Daily Mail, John described his mother as fiercely independent, "My mother raised all the boys with such grace and strength."
"Especially now that I'm a father of two trying to do the best I can, I truly admire her more than ever."
He added that the one piece of advice that stuck out the most to him from his mum was to seek solutions rather than lament when faced with an issue.
John also sadly lost his father in November 2016, with the TV star taking to Instagram a year after his death to share a tribute.
"Thinking of Dad today. 5th January 1933 – 29th November 2016. Missing you," he shared.
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