I am searching for my mother-in-law's birth parents.

What I know is that MIL, Ruth Ann Wiiks was born at St. Therese Hospital in Waukegan, (Lake County) IL on October 26, 1958. She was adopted by Merv and Eunice Wiiks that did not go through courts, so I do not believe there is any court record. My brother-in-law says that Ruth knew her mother's name and told brother-in-law, but she was in poor health and hard to understand, but he believed it was Helen Hollingsworth (or Helensworth, or some similar spelling)

What I don't know is if she was born Ruth Ann or if that was later changed. I do not have her birth certificate and I don't believe I can access it, because her parents are no longer alive, the person legally responsible for her estate is unwilling to assist and the record is not 75 years old yet.

I have not been able to locate any sort of birth announcement in newspapers. Her husband is not willing to assist.

Where else can I look to try to find something? Any help appreciated.