But she's put it all behind her now and is apparently very pleased that Kimmy K is pregnant and expecting her first child.
American site TMZ reports that the heiress was heard saying: ''So happy for her, they are perfect for each other'', when a friend broke the baby news to her whilst she was out shopping.
Paris and Kim, who are both socialites in the same crowd, have had their differences in the past.
But the girls made up recently and were spotted partying together in Miami.
It could be something to do with the fact that Paris is pretty loved-up at the moment herself.
The 31-year-old has been enjoying a whirlwind romance with her toyboy boyfriend River Viiperi since September.
The pair enjoyed a romantic skiing trip in Aspen last week, before heading to Miami for New Year.
Meanwhile Kim Kardashian's brother Rob Kardashian has also sent his well-wishes to her and boyfriend Kanye West at the news that they are expecting.
He said: ''It's beautiful. It's a blessing. The New Year, we've got another child coming, so that's great. Kim's never had a baby, so it's going to be a beautiful blessing.'
[Related story: Kim Kardashian says pregnancy isn't easy]
[Related story: Kim Kardashian & Kanye West celebrate pregnancy news with by NYE]