Hilary Duff and son Luca had a blast in the audience for Justin Bieber’s recent Los Angeles concert, and the “How I Met Your Father” star shared the experience with her 20.3 million Instagram followers.

In her post, Duff shared some photos and video of herself and her 9-year-old son as they sing along boisterously during the show, which took place at Los Angeles’ Crypto.com Arena on Tuesday night.

In the videos, she and her son — whom she shares with ex-husband Mike Comrie — are seen joyously rocking out, singing along with The Biebs during the L.A. stop on his Dignity tour.

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“The. Best. Time,” Duff wrote in the caption, tagging Bieber.

“I think this is the last year Luca will put up with this out of me so I sang reaaaaaal loud 😭😭😭,” she joked.