Representatives of the Pima County Genealogy Society discuss why and how to compile family histories using resources available at home, the internet and across the country, from 1 to 3 p.m., Saturday, Oct. 26, at the Mission Library, 3770 S. Mission Road; and at the Murphy-Wilmot Branch Library, 530 N. Wilmot Road; and at 3 p.m., Wednesday, Oct. 30, at the Himmel Park Library, 1035 N Treat Ave; free.