'Baywatch' actress Kelly Rohrbach and Walmart heir Steuart Walton may be planning $1.5 million wedding

Next time you're on a long train ride, mute your headphones.

In a series of now-deleted tweets, author Cat Marnell said she sat across from Walmart heir Steuart Walton during a recent five-hour train through Switzerland. As the train chugged along, Walton allegedly spilled details of his million-dollar wedding through multiple revealing phone calls, according to Page Six.

The 38-year-old billionaire has been dating "Baywatch" actress Kelly Rohrbach, 29, since spring 2017. Rohrbach was on the receiving end of at least one of Walton's calls, Marnell claimed -- and despite Walton's massive fortune, their wedding budget reportedly maxes out at $1.5 million.

Marnell was "listening to him call fiancée Kelly Rohrbach" before Walton ended the call to "b--ch out ... their wedding planner. Actual quote: 'A $20k sandcastle is not required to have a good time.'"

According to Marnell's subtle spying, the two plan to wed on Harbor Island in the Bahamas.

"He also called his lawyer ... and worked on his prenup or life insurance policy," she wrote, quoting him as saying, "'I don't want to incentivize my death.'"

Both Rohrbach and Walton are Georgetown grads: Rohrbach went there for undergrad while Walton attended for law school.

Walton's grandfather, Sam Walton, opened the first official Walmart in 1962 after several years of purchasing and managing small stores throughout Arkansas.

Rohrbach, who previously dated Leonardo DiCaprio, became Sports Illustrated's Rookie of the Year in its 2015 Swimsuit Issue.

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