Randi Zuckerberg, the sister of Facebook founder Mark Zuckerberg, got caught up in a debate about the handling of a private photo posted on the social media site after a family snapshot she thought she had only shared with friends made its way onto Twitter.

The photo showed the Zuckerberg clan joyfully reacting to Facebook’s new Poke app.

Zuckerberg, Facebook’s former head of marketing, claimed she had only shared the photo with her friends via the social media site.

However the snapshot went public after Callie Schweitzer, a representative for Internet media firm Vox Media, reposted the shot on Twitter.

According to BuzzFeed, early Wednesday morning Schweitzer tweeted: "@randizuckerberg demonstrates her family's response to Poke," and included a link to the picture.

The older Zuckerberg then quickly replied "@cschweitz: Not sure where you got this photo. I posted it only to friends on FB. You reposting it on Twitter is way uncool."

The photo was promptly deleted and Schweitzer apologized, explaining that she had seen the photo on her Facebook newsfeed.

“Genuinely sorry but it came up in my feed and seemed public” she tweeted.

It was later determined that Schweitzer is Facebook friends with Randi Zuckerberg’s sister, who was tagged in the shot, giving her access to the photo.

Zuckerberg, now the executive producer for a Bravo reality show on Silicon Valley, then thanked Schweitzer for the apology and added that she is sensitive to private photos becoming “news.”

However, she stopped short of citing Facebook’s sometimes confusing privacy settings as the reason behind the mix-up.

Later Wednesday, she tweeted: “Digital etiquette: always ask permission before posting a friend’s photo publically. It’s not about privacy settings, it’s about human decency.”

Earlier this month, Facebook began rolling out new privacy tools to help users control who can see their photos and posts.

Some of the changes include privacy shortcuts and a new removal tool to help manage multiple photos users are tagged in.

A statement posted on Facebook said the company is also implementing “in-context reminders” to the site, which explains to users how content hidden from their timeline may still appear elsewhere on the site, such as in newsfeeds.