Ive noticed some generalised rules in looks.
1. the first born child looks like the parent of the opposite sex, the next and subsequent child looks like the parent of the same sex.
2. if the above rule isnt obeyed, the firstborn tends to look like the grandparent of the same sex, and the subsequent siblings look like the grandparents of the opposite sex.
ofc, it isnt always true, its very complex, but it works as general rule.