They seem to look like their parents to me, if the mother was the one on the top left and father is the one in the checkered blue shirt. I find it easier to pick out family traits on the family screen where you can see the close ups of their faces. If you go through the family screens in this thread you can sort of reverse-engineer the genetics at work.

My only blonde family member, for example, was adopted, and mom and dad have red / brown hair and blue / brown eyes. so the kids tend to have a mixture of their hair color or darker, but not lighter, and would have the eyes of one of the parents.