According to the NY Post, Charlie Sheen's future ex-wife Brooke Mueller was on the set of Charlie's new commercial he was shooting and kept taking pregnancy tests and putting them on top of the trash. Besides a desperate cry for attention, what this shows to me is that she knows the only way to get whatever is left of Charlie's money is by having a kid. Despite the big rock on her finger, there haven't been any wedding bells. I'm not sure there will be any wedding bells, but if she gets knocked up, then just maybe.
BUT, even if they don't get married, and she gets pregnant, she will get paid. Now, I for one am totally not in favor of a woman doing this except in this case. She has put up with so much and basically just bent over backwards even outside the bedroom to make it appear as if they are a loving couple. She has played nice or mean with Denise Richards depending on the circumstances. She has leaked little bits of info for Charlie and has stood by him even with all the unseemly portraits that Denise has painted.
For this she deserves something, and if she thinks the only way to get something back for her investment is having a child, then go for it. Just don't expect Charlie to be interested in the kid until she is about 14 or so.