Isla Fisher has broken her silence after Confessions of a Shopaholic author Sophie Kinsella died at the age of 55.

“Dear Sophie, you conjured Rebecca Bloomwood, a hilarious flawed dream of a comic character,” Fisher, 49, wrote via her Instagram Story on Wednesday, December 10. “I was lucky enough to step into her shoes and speak your witty and brilliant words.”

Fisher starred as the titular shopping fiend in the 2009 film adaptation of Confessions of a Shopaholic opposite Hugh Dancy. Kinsella published her novel of the same name in 2000.

“My daughters grew up being read your books and love them to this day,” Fisher, who shares three kids with ex Sacha Baron Cohen, added in her note to Kinsella. “My heart is broken. You’re still my hero, and I’m grateful for you.”

Celebrity Deaths of 20

See Full Page