It's been a rough month for hotel heiress Paris Hilton. First, her Hollywood Hills home was burglarized and now her pet Chihuahua, Tinkerbell, has disappeared.

Hilton, star of the Fox reality show The Simple Life 2: Road Trip, is offering a $5,000 reward for her dog, missing since last Wednesday, Hilton's spokeswoman, Tracy Shaffer, confirmed Tuesday.

It's unclear how the dog managed to get away.

Tinkerbell - decked out in pink coats or puppy-sized sneakers - has made regular appearances on Hilton's reality show.

Posters for the pampered pet were displayed all over the West Hollywood area.

Hilton, 23, and her sister, Nicky, reported the home they share in the Hollywood Hills was burglarized on Aug. 5 or Aug. 6 and jewelry and cash were taken.

Paris Hilton was set to begin shooting for her first starring film role in Pledge This, about a college sorority, this month.