Are Shia LaBeouf and Mia Goth Engaged?

Are wedding bells in Shia LaBeouf and Mia Goth’s future?

The actress was photographed attending the Miu Miu show at Paris Fashion Week on Wednesday sporting a huge rock on her ring finger. A rep for LaBeouf hasn’t commented.

The Nymphomaniac: Vol. II costars have been linked since 2012, and engagement rumors have been floating for the past few weeks as Goth has been spotted out wearing the sparkler.

While they’ve yet to announce any official engagement, a source tells PEOPLE that “they seem very happy and spend a lot of time together. Shia is a big goof and Mia is the same way. They are usually just laughing and seem to have a great time.”

She now lives with LaBeouf at his home in Sherman Oaks, California, the source says, and “they live pretty simple and enjoy casual dates like picking up frozen yogurt, and at night they mostly stay at home.”

Congrats to the happy couple! Maybe.

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