I can not bit and turn my elderly alien sim into a vampire..

[xxdarkntwistyxx]

I have a favorite sim that happens to be an alien.  He just reached elderly status so I thought, "Hey, why don't I just use my vampire (who is maxed out) to bite this guy and turn him so he can live forever!".  I befriended this favorite sim with my vampire all the way to best friend status and the option to offer to turn him will not show up.  I went under vampire options to just turn him anyways and the option to turn him is not showing up.  I jumped onto a different vampire I created and ended up with the same results.  I thought maybe because this favorite sim is elderly?  I used the cas.fulleditmode and turned my favorite sim back down to an adult.  Still no luck.  I still can't bite and turn him.  I played my favorite sim and had him talk to my vampires to try to get the "ask to be turned" option to appear but it never did.  I'm stuck.  I can bite and turn any other sim but not my favorite sim.  Any ideas?

[crinrict]

It's most probably due to the fact that it's an alien. You can't have hybrid Sims so Aliens can't be vampires as well.

Best is to try if it works on a normal Sim and if it does, I think that's the issue

If you're not opposed to mods, you can give the MC Command Center a try. That does allow alien/vampire hybrid but I'm not exactly sure how you get them with the mod.