Talk about stealing somebody's thunder!
In the touching video, filmed on a hidden camera by Australian teenager Hayden Smith and uploaded to YouTube, the boy opens up to his mother about his sexuality.
Her reaction throughout the film is wonderful. She strokes her son's face and tells him that she loves him no matter what, that she understands, and that everything will be OK.
But around 5 minutes into the 10 minute 28 second video, the mum drops a little bombshell. She says she has a secret of her own, and asks: "Can I tell you something too?"
Story continues after video...
She then goes on: "I've had a girlfriend."
Her son looks at his mother in stunned silence with a look of pure 'WTF!' on his face, before she explains that she had the relationship before she was married to the boy's father, who has since passed away.
The video ends with more words of love and affection from the teenager's mum, but when she tries to hug him he says: "No way!"
For a teenager, your mum coming out to you on film is one thing - but having her hug you for nearly 400,000 YouTube views to see is another thing altogether!
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