My sister-in-law was adopted from the Hillcrest Family Services in Dubuque, Iowa back in December of 1967 (birth in November) and we do know that it was a closed adoption and she has since received a few tidbits of information like height of parents, nationality and ages.

Is there any way to find ANY information about her parents or any references that I could search for? It is something that it would be of great help for her to know more of where she came from.

Thank you for any help you can provide.
Heather