What’s got Tom Sandoval and Ariana Madix all riled up on the upcoming episode of Vanderpump Rules?

Is ‘Vanderpump Rules’ Couple Tom Sandoval & Ariana Madix Headed For Marriage?

In a sneak peek at the new episode, Sandoval announces plans for a joint birthday trip to his co-stars, and while the idea is exciting, drama quickly erupts after Kristen Doute’s possible appearance is brought up by Tom Schwartz.

“I don’t even know why we would talk about that,” Sandoval responds.

‘Vanderpump Rules’ Ariana Madix Shuts Down Tom Sandoval’s Vegas Plans: ‘I Will Cancel My Whole Birthday’

“That definitely wouldn’t make anybody’s trip more fun. That’s for damn sure,” Madix says, adding that the only person who should be able to determine if enough time has passed is her, and not one of her co-stars.

“It’s common knowledge that Kristen is an emotional and mental liability. Why am I being questioned?” Sandoval asks in his confessional.

Then, when Katie Maloney calls Sandoval “Stassi,” he loses it.

“What do you mean ‘Okay, Stassi?' Am I giving you ultimatums, Katie? Are you f**king kidding me?! You are tying to make me look like an a**hole because I’m having a birthday and I don’t want to invite her? Why are you even bring it up?"

For more of Ariana Madix and Tom Sandoval, tune into Vanderpump Rules season four, airing Mondays at 9 p.m. on Bravo, and check out a sneak peek below.