What happens when your alien sim and vampire sim have children

My Alien male Vampire female couple had a normal human child. What's up with that?  My alien does have a human mother, but he has all the powers of his dad. All of his other siblings are listed as part alien in their log files from MCCC. 

@MiladyRevenwyn, the genetics and abilities for Alien/Vampire hybrids are tricky🤨 , often causing the offspring to be a bit glitchy because the bottom picture in the thumbnail in CAS for Aliens is the Alien Form, and for Vampires it is the non-Vampiric form; while for the top thumbnail in CAS for Aliens is the Alien Disguise and for Vampires it is the Dark Form.  You can see the glitch in these CAS pictures:

Alien Form / Non-Vampiric form

Alien Disguise/Vampiric Dark Form

Skin color is Alien but the Vampire "smoke" shows up as well.  Oftentimes when leaving CAS, any changes you made don't' stick for either form. ☹️

But with genetics in real life, not every trait will get passed down anyway.  My thought is that the game is replicating this in its own way.  However, Vampires are really specialized humans.  Aliens are not.  So it could be that your hybrid child received the underlying human form from its mother and the human part of its Half-Alien father, resulting in a Human Sim.   The siblings must have all had the inherited the Alien part  from their Alien/Human hybrid father, and only this one child received his Human part (at least so far... this might happen again if the couple have more children!).  Since the father has both Alien and Human genes, he can pass on either to his offspring. 🤨😉

@RogueToad16, yes, I would like a way to influence that too, like we can with getting a boy or a girl when our Sims are pregnant. 🙂 But my guess is that the developers really didn't intend for us to be mixing Mermaids/Aliens/ Vampires so they didn't add a way to influence by food or radio station, like you can with gender. 🤨

I have a alien vampire daughter because my character is a master vampire and was abducted by aliens..He gave birth to her himself lol 

@waltmisse, LOL, I have a similar situation in one of my saves! 😃 He's not a Master Vampire yet, though.  But he did get abducted and gave birth to a little girl.  However, before he was abducted, he drank from Ted Roswell from Strangerville, and I forgot that Ted was infected/possessed! 🤭  Ted passed his condition along to my Vampire! 🤨 Then my Vampire was abducted and impregnated... I don't know if the baby will be infected/possessed when she is a teen or not. 🤨🤔  I need to revisit that household and age her up to see what happens! 🥳

My Vampire sim just gave birth to a vampire alien hybrid 

I made a male vampire and a female alien be in love, and when they had a baby, it was a half-alien half vampire...

I'm lucky I got a alien baby and also a vampire baby first try twins so I guess it's the luck of the draw