Hilary Duff is mourning the loss of her tiny Chihuahua, Lola. The Two and a Half Men guest star shared news of her pup's passing via Twitter on Tuesday, June 25. "RIP my beautiful Lola girl. My heart is broken. Say a prayer for my little angel."

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Duff's dog had been battling health issues for years. In 2011, Lola was rushed to the emergency room with an eye infection. The following year, the actress' pet underwent brain surgery. "Lola was having terrible seizures," Duff explained on Twitter. "She had a shunt put in her [skull] to drain fluid off her brain and now is doing great."

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The Lizzie McGuire vet (and mom to son Luca, 15 months, with husband Mike Comrie) thanked her Twitter followers for their kind words following Lola's death. "Thank you for all your well wishes for my beautiful Lola," the 25-year-old star tweeted. "It really means so much when you [are] hurting to know so many people care."

This article originally appeared on Usmagazine.com: Hilary Duff's Dog Lola Dies: "My Heart Is Broken"