The 'When You're Gone' hitmaker had fun at the Bellagio Hotel in Las Vegas alongside some female friends on September 27, reported E! Online.
Wearing a strapless pink dress, Lavigne celebrated her birthday alongside her sister-in-law Amie Lavigne and best friend Caryn Alpert at The Bank nightclub. She matched her dress with a pair of nude-coloured pumps and beautiful bracelets.
The singer and her husband whom she married 14 months ago are reportedly having marriage problems. Earlier this month, a source said the couple has been fighting a lot and having a lot of issues.