Charlie Sheen will "absolutely" have a pre-nuptial agreement before he marries Brett Rossi.

The Anger Management actor - who has an estimated fortune of $125 million - plans to be "generous" towards the porn star in the event their marriage doesn't work out, though he doesn't think the financial contract is necessary because he sees her as his "soulmate."

"Charlie will absolutely be getting a pre-nup, just in case. The pre-nup will be very generous for Brett, but Charlie has to protect his finances even though he doesn't think the agreement will be needed, because he believes Brett is his soul mate. It's likely Charlie will pay for Brett's legal fees as they work out the details of the pre-nup. For him, this is only a formality. He doesn't think Brett is after his money. This time, it's different," a source said.

Charlie's third wife, Brooke Mueller - the mother of his four-year-old twin sons Bob and Max - received a $500,000 payment when the couple wed in 2008 and $500,000 for each year they were married, as well as $100,000 in relocation feeds and $2.35 million for her share in the actor's Beverly Hills mansion.

And the former Two and a Half Men star is expected to be even more "generous" in his agreement with Brett, 24 than he was with Brooke, who he split from after less than three years together. "Charlie will be a little more generous with Brett in regards to the pre-nup, than he was with Brooke," the source said.

Charlie was advised to draw up a pre-nup with second wife Denise Richards but refused, though she does get $55,000 in child support for their daughters Sam, nine, and Lola, eight. "There wasn't any need at that time because he just didn't have a lot of money. The Two and a Half Men money came after the marriage ended," the insider said.

Charlie married for the first time in 1995, to Donna Peele, but they split a year later.