The 25-year-old has reportedly booked a plot in Hollywood's Pierce Bros Westwood Village Memorial Park next to her screen idol.
It is also alleged that she has booked a gospel choir to perform at a private funeral at Los Angeles' International Church of Christ.
A source told Britain's Daily Star newspaper: "It's absolutely disgusting. Paris booked the plot for a 'Billy Hilton'.
"Everybody was very understanding because they presumed it was one of her relatives.
"But it has transpired that it's just an old goat. Normal people are content to bury their pets in the garden and be done with it. But not Paris.
"This is one of the most prestigious cemeteries in the world, it's not for animals.
"It should be reserved for superstars." Hollywood legends Truman Capote, Dean Martin and Jack Lemmon are also buried in the cemetery.
Paris offended Marilyn fans last month when she told Britain's Guardian Weekend magazine: "I think every decade has an iconic blonde, like Marilyn Monroe or Princess Diana.
"And right now, I'm that icon." The animal loving hotel heiress has many pets including two chihuahuas, a ferret, a monkey and a goat called Billy.