Looking for Female Gucwa girl born in 1950's

Looking for a woman who was born sometime in the early 1950's who was given up by a woman by the name of Evelyn Gucwa. Mother lived in Rhode Island. This woman went looking for her birth mother many years ago as she found the uncles and aunts but they would tell her nothing. I am helping my cousin who wants to find his half sister! I do not know what her first name or adopted name was. It is my understanding she does know that her birth mother's last name was Gucwa. Any help in finding this person would be much appreciated.