How to pass CC onto Kids?

So basically what the title says, I'm wondering if there's a way when your two original Sim are modded the kids will then inherit there features/look. You know skin colour, hair colour. I have downloaded the same Custom Content for toddlers/kids/teens where possible but it never seems to happen.

I have this Male Sim.


And this Female Sim.


They have had 5 kids and each one has been completely different, blonde hair, skin 5 shades darker, red hair. It seems like a genetic lottery. I know I can change them all to what I want in CAS but its just gets frustrating.