David Beckham Made Fun of Victoria Beckham's Teeth in a Rare Smiling Photo

It is universally acknowledged that Victoria Beckham rarely smiles in photos (even Beckham herself has talked about it), so when she does, it's cause for notice — in this case, with a picture on her son's Instagram page.

On Tuesday, 15-year-old Cruz Beckham shared a photo of himself with his grinning mother, writing, "Apparently my mum does smile."

The photo prompted a reply from David Beckham, who poked fun at his wife's teeth in a comment: "How white are mums @victoriabeckham teeth ? it’s Ross from friends," adding a laughing emoji.

For those who don't remember, the comment refers to one of Friends's most memorable episodes, in which Ross has a snafu involving some teeth whitener.

Honestly, bonus points to David for the reference.

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Victoria previously poked fun at the rumor that she never smiles, and referenced her reluctance during an interview with Glamour UK last year: “I want to be honest. In the past, I’ve probably hidden behind my armor – the not smiling publicly, for instance. There’s less of that now."

“There’s something really liberating about embracing who I am at 45 years old and owning it, feeling confident, feeling content," she said. "Doing beauty has really helped with that – it’s been very liberating. I want to spread the word that everybody should feel like the best version of themselves. To look after what you have. I want to tell people to own who you are. Yes, we – and I – have wrinkles, and that’s OK!”