In five generations all I had were black haired families. So I took an adopted girl with brown hair and married her up to a guy with blonde hair. And together they made two childen with purple and green hair.

Yeah - that happened to me with the same hair combination. It was very amusing, as I was attempting to create a "traditional" family ... the kids clearly ended up rebelling. Go figure.

I'm doing some experimenting now to see what hair color breeds what other colors. My strangest has been my blond husband and wife having a black-haired child! No, he wasn't adopted! I'm especially interested in seeing what the hair on the kids look like with a rainbow-haired mother. My peeps have never produced a rainbow-haired child...

Right now the Mom (blonde) and husband (brown) had a purple and red/black haired children.

The rainbow haired girls are the hardest to get, seeing as they're rare and they're at the end of the scale.

As I've stated before, I haven't gotten a rainbow haired child after several generations so I started 2 new games using rainbow haired girls and they married brown haired boys. They produced blonde kids. Their grand kids however had purple, green, and really red hairs. Now I'm waiting for the blue and black haired girl. Tried adopting her when I started my other games but she never showed up. I'm just gonna wait for my families to produce a daughter with that hair. Saw that Lukerie got them in one of his families.

The way to know what hair colors your peeps will produce in kids is to take the mom and dads heads count the heads between them, and the heads in the halfway area between the two are the kids they will have. Sometimes too, the heads two-three rows above or below either will become their kids. It doesn't always work this way but is the norm. I did have two black haired parents who produced a blonde hair blue eyed boy once.

Is there a chart somewhere to figure out the hair colors?

From what I've seen, the rainbow-haired girl is at the blond end of the scale. She's also one of the extremes (people who can only be obtained through adoption or through mutations in the family)

Mutations in the family explain how two blond haired parents have a black haired child sometimes. It's not a usual thing, but it happens.

Lewanda is referring to the head image file in the game's image folder.