Rihanna dresses as Pebbles Flintstones at her niece birthday party

For her cousin Noella Alstrom's daughter, Majesty first birthday party Rihanna impersonated Pebbles from the Flintstone.

The singer donned a sexy orange and black asymmetrical off-the-shoulder dress with trademark bones in her hair.

One of her friends uploaded a clip of RiRi to Instagram saying: "They call me ratchet Wilma. And this is naughty Pebbles."

The party was themed after popular Hanna-Barbera cartoon The Flintstones, which also has live-action film adaptations.

Rihanna with cousin Noella Alstrom and daughter Majesty at first birthday party