Though they kissed like a reunited couple at a pre-Grammy gala, Amber Rose insisted she and Wiz Khalifa weren't back together. Even so, the former couple took the time to celebrate their son's fourth birthday by dressing up in Batman costumes.

Sebastian Taylor Tomaz looks ecstatic with his Joker makeup as his parents pose and dance with him on the Instagram photos uploaded on Wiz's account. The Pittsburgh rapper put up a kaleidoscopic image of his son and himself on his IG account.

Though Rose and Wiz divorce in 2014, they have joint custody of their son Sebastian. The Daily Mail reports that guests at the star-studded house party included Lamar Odom and Blac Chyna. 

Check out some of the pics from the birthday bash below.

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A post shared by Wiz Khalifa (@wizkhalifa) on

A post shared by Wiz Khalifa (@wizkhalifa) on

A post shared by Wiz Khalifa (@wizkhalifa) on

A post shared by Wiz Khalifa (@wizkhalifa) on

Hangin with my dude @wizkhalifa at Sebastian's birthday party. #wutdadeal

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