Half Alien Baby Question

It will be a hybrid. The baby will have the skin color of the alien parent.

Hello.
This link explains about alien children and pregnancy.
http://sims-online.com/aliens-sims-4-get-to-work-male-pregnancy/

I can use that lol

Even though this wasn't my question thanks!

If your talking about human skin tones yes they can have a non alien child.

I have made a half Alien half human baby on the sims 4 without mods just one simple cheat he looks fully human and on the create a sim menu it’s gives and option to add a disguise but mine doesn’t have one but he has human eyes and skin sounds human doesn’t get noticed as being an alien and he has all the abilities and traits

In vanilla games, interspecies couples will always have hybrid children (if one of them is an alien. Couples with one Vampire will always have one or the other). However, you can use MCCC to set it so that they can have either human, alien, or hybrid offspring or some combination of the three.