Actor Charlie Sheen's ex-wife Brooke Mueller "adores" his fiance Brett Rossi and is "ecstatic" they're getting married.

Mueller, with whom he has five-year-old twin boys - Bob and Max - is thrilled that Sheen is marrying former porn star Brett Rossi because they get on really well, reports contactmusic.com.

A source told gossip website RadarOnline.com that the 36-year-old socialite, who has been to rehab for cocaine addiction more than 20 times, is "ecstatic over Charlie's choice for a future wife".

"She is so happy. Brooke has repeatedly been over to Charlie's house with their sons, Bob and Max, and she and Rossi have truly hit it off,` said the source.

"Brooke has even chided that Charlie is an amateur compared to her and she would 'pinch hit' for Charlie with Brett in a second if she got the chance,` the source added.