Looking Roberta Lucille Potter Jones -

I am looking for my mom's sister, Robert Lucille Potter Jones. She was given up for adoption to my grandfather's sister, Mary Potter and her husband Earl Jones. She was last seen when she was 12 years old in Los Angeles, CA on a visit to my grandmother, Keziah Emmaline Martin in 1950. Unfortunately, grandma died before she ever saw her again and now my mom, Phyllis Potter Jones would like me to locate her. The family is originally from Kansas City, Missouri.

Any help would greatly be appreciate, since we have lost all contact with any family back in Missouri or Kansas.