Help me find missing ancient stocks

My greatgrandma bought my mom AT&T stocks at least 50-55 years ago when my mom was a kid. My mom doesn't know how many shares that was and where exactly were they held - but assuming it could sum up to a lot of money, me and my mom would like to find them. Any help would be appreciated 🙏 submitted by /u/Effective_Knee_3401 [link] [comments]