People thought Ryan Gosling was dating his sister last night

The La La Land / Moonlight Best Picture fiasco wasn't the only Oscars mix up involving Ryan Gosling last night.

The superstar arrived at last night's Academy Awards with a woman who was not his wife of six years - the exceedingly talented Eva Mendes.

Gosling and Mendes at 'The Place Beyond The Pines' premiere, 2012

The couple married in 2011, and have two daughters - but are not often photographed together, preferring to keep their relationship private.

So when Gosling attended the Oscars with this woman, Twitter had a lot of questions.

Picture: Getty Images / Kevin Winter

A heroic FAKE NEWS fighter quickly stepped in to calm the storm.

Correct. Go to the top of the class.

The blonde woman photographed with Gosling is his sister Mandi, who has often joined him at red carpet events in the past.

Picture: Getty Images / AFB / Timothy A. Clary

Picture: Getty Images / Michael Buckner

In fact, many of the tweets about her during the Oscars focussed not on her anonymity, but on her breasts.

Just to double check, this is 2017 right? Show some respect.

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