I know this might sound kind of crazy, but I think that unlike in real life, the Sims 4 way of choosing the genetics of a child largely depends on the mother's traits. I made some tests, and made two sims. In the first trial the mother had blonde hair and blue eyes, while the father had black hair with black eyes. While still in CAS, I created 5 children via the genetics, I made them all female for it to be consistent. 4 out of 5 were blonde and blue-eyed. In the second trial I switched it around, I made the mother have black hair with brown eyes, and the father have blonde hair and blue eyes. 1/5 or the children had black eyes and 3/5 were black-haired.
Does anyone think this is possible or was it just this one time that it decided to work like this?

It's a pity how little family lines matter anymore. It's a missed opportunity. They could have passed down things like traits that eventually unlock deeper traits as the family tree expands. Heck even before, doing well in school gave you some extra traits.
Now... you might as well not bother.. because school really doesn't matter.

But I can't really put all the blame on EA or the sims. It's a problem within the entire industry. Simplified "dumbed down" games are now par for the course.

To be honest,

Genetics after the Sims 2:



Lots of people just edit their sims after they age up anyways.

Usually hair color is passed down from the mother's side tho irl.

Um no. Hair color is very complex even the traditional dominant/recessive traits isn't very adequate to explain hair color. Same for skin color too actually.

I personally am a little frustrated with the 'genetics' in game.

Sims 2 may not have made the prettiest combinations of the parents (at times) but at least the child was visibly similar to both mother and father For a red-haired mother with green eyes and a black-haired father with grey eyes, I wound up with three kids with red hair and grey eyes, two children with black hair and green eyes, and one with dark brown hair and blue eyes (which came from her maternal grandfather and paternal grandmother as they each had blue eyes with one having dark brown hair and the other having blonde hair). The child of the oldest daughter had grey eyes and brown hair.

In Sims 4, I created the same couple. However, every child has red hair and their eyes seem to be completely random, varying from blue to purple to brown. I tested it further with a third generation, introducing black hair again to see if that would darken the hair color in the family and brown eyes. The child from that once again had red hair and had black eyes I don't see how the maternal grandparents with green and grey eyes, the paternal grandparents with blue eyes, and the daughter with purple eyes and her husband with brown eyes had a black-eyed child? Not to mention, with varying hair colors in different generations/relatives: red, black, dark brown, blonde, and brown, how every child of the original couple can have red hair? I know I can edit it in CAS but I haven't ever seen a family where every generation has the same color hair. All of the kids born from my original couple have the red hair and so far, all their children do as well, no matter what hair color their other parent has.

Genetics SHOULD NOT require a lot of overhead, especially in TS4 where there's a lot less going on. Simplified genetic math is quite easy. A punnet square takes some (very light) work, but details like that requires a designer to actually care about those details.

Genetics are just numbers. Anything genetic related should be possible in TS4 as it was in TS2.

Sims 2 also has proper genetics. If a sim is born with black hair and dyes it blonde, she never gets blonde genetics. Its just hair dye. In 3 (and maybe 4?) whatever color their hair is at the moment is the color they pass on.

Genetics is not just about hair or eye colour or shape of face though. I am rather amused that my sim founder's belly gets passed down to his sons and grandsons. I must have made my founder from a fat sim in CAS so he has a bit of a belly going on even though he is very fit and muscular. That slight pot belly is my sims' heritage.

By the way, there was a problem in Sims 2 with brown eyes if anyone recalls. I remember having to use a mod to give my sim kids a chance of getting different coloured eyes if one parent had brown eyes. The genetics system was far from perfect.

It isn't perfect, but it is certainly the best attempt at genetics in the series. Most of the little flaws can be modded out.

It wasn't that it was perfect, it's that it was there.

I can see it now, it'll be an upcoming pack: Sims 4: Get Genetics

I know it's really complex. When I made that comment I was making a generalization. Maybe EA used the same generalization.

I've noticed that a ample sized bottom can be passed on from father to children. Of my favorite family, all four children have inherited the fathers eyes, 2 have his nose, 2 have his lips, all 4 have his chin. I find the children only slightly better looking in Sims 4 compared to Sims 3. I'm a little annoyed with the eye color inheritance. I know brown is the dominant gene but that doesn't mean its impossible for a brown/blue couple to produce at least ONE blue eyed child! My own mother has blue eyes and her mother had brown!

In my second family that I play, 2 children have the fathers eyes, all three have the mothers nose, 2 have the mothers lips.

My biggest issue with sims genetics has always been how the facial shape can end up so messed up. A son might inherit the mothers jaw shape and fathers cheekbones end up with a really small receding jawline and bizarre jutting cheekbones. Looking awful and requiring a cheat to fix.

There is no problem with brown eyes in sims 2. They and dark blue eyes were just made to be dominant over green, grey and light blue eyes like irl. Same as black and brown hair are dominant over red and blonde hair which is exactly the same as irl.

I think it's probably just 50/50, and that was coincidence. I actually don't mind the Sims 4 genetic system, although if they put more effort in to give things recessive/dominant genes or work on a Punnett square system, it would really be something to be proud of.