A source tells E! News the exes ran into each other at the Playboy Midsummer Night's Dream party over the weekend, and, despite partying right next to each other, were totally cool.
"[They] were partying just a few feet from one another," the source told us. "Bella came with her sister and Gregg came with a male friend."
We're told the two "chatted briefly" before going off and doing their own thing. Gregg was photographed with Tyler Posey at one point, wearing a superhero-themed robe.