Can't manage to get a ghost baby

[AllIWannaDo]

My female Sim is a vampire and her fiance is a playable alien ghost.  When trying for a baby with a ghost did not yield a ghost baby, I had my female Sim take the ghost potion prior to trying for a baby with said ghost.  This, too, has failed twice so far.  Both babies are normal alien babies.  Can anyone tell me what I'm doing wrong? 

[kittenalive]

Well, when I did my ghost baby thing, I used a normal sim and her dead husband. I figured that until I had reanimated him that I coul have a ghost child and when the achievement, you know? But mine worked on the first try. I don't think you're doing anything wrong. But I'm actually quite surprised you managed to get an alien partner, I can never get those.

[AllIWannaDo]

Well, when I did my ghost baby thing, I used a normal sim and her dead husband. I figured that until I had reanimated him that I coul have a ghost child and when the achievement, you know? But mine worked on the first try. I don't think you're doing anything wrong. But I'm actually quite surprised you managed to get an alien partner, I can never get those.

Thanks for responding!
I suspect that I haven't gotten the ghost baby because the alien DNA is too strong.  After all, most of the kids the female Sim has had with her lover have been aliens, despite the fact that she's a vampire.  So I'm going to try for baby with a human ghost Sim and see if that makes any difference.
Also, it actually wasn't very difficult for me to get an alien lover.  (Maybe I just got lucky?)  After using my telescope for a few nights and leveling up my logic skill (I was trying to get abducted, but alas, that never happened!), I noticed an alien outside my house.  I invited him inside, made his acquaintance, and was afterward able to invite him over.  From there on their relationship developed like that of any two Sims.

[kittenalive]

I actually just ended up meeting an alien and was trying to do the same. However, one evening when I was flirting with him he suddenly died of old age. So now I have an alien ghost living at my house

[AllIWannaDo]

That's actually pretty cool!  My alien was an elder, too, but it took him forever to die.  He was at the end of his life span when I had him move in, but he didn't die until about two weeks after that.  And then his ghost only visited the house once, so I had to wait for the Oh My Ghost! opportunity to get him to stick around longer.  It was a bit annoying, especially since I wasn't able to get a ghost baby regardless.   

[kittenalive]

Yeah, I still have to try to make a baby with him so hopefully he'll come around more often lol