All from familysearch.org.Fidelia appears to have had 2 children - Ida and Albert. In 1900 she is a widow, but has a stepdau, Minnie, living with her also.Looking for Minnie - found her with parents Noble and Isabelle in 1880, and grandfather Augustus, so Noble must have married Isabelle prior to Fidelia.Maybe the dates on the census data will help you find more.
Not my family, good luck.
US Census, 1880 Erie, Whiteside, IL
selfNoble Eddy M 42 IL wifeIsabelle Eddy F 42 NY dauMinnie EddyF 7 IL otherAugustus Eddy M 80 VT
U S Census, 1900 ED 142 Erie Township Erie village, Whiteside, IL
headFidelia M EddyF 51 IL/NY/NYwidowed 2 children 2 living sonAlbert N Eddy M 16 IL dauIda D Eddy F 17 IL stepdauMinnie E Eddy F 27 IL
U S Census, 1920 East St Louis Township East St Louis City Ward 6, St Clair, IL
selfEdward C Ferguson M 36y IL wifeIda Ferguson F 36y IL dauFidelia Ferguson F 15y IL dauMarguerite Ferguson F 13y IL sonEdward Ferguson M 12y IL mother in law -Fidelia EddyF 72y ILwidow
U S Census, 1930 East St Louis, St. Clair, IlL https://familysearch.org/pal:/MM9.1.1/X3M4-148
headEdward C Ferguson M 47 IL wifeIda T FergusonF 46 IL sonEdward M Ferguson M 22 IL dauMargerite Rhymes F 24 IL stepsonEdward Rhymes M 5 IL? maybe grandson and not step
US Census, 1940 Tract SCC-6, East St. Louis, East St. Louis Township, St. Clair, IL https://familysearch.org/pal:/MM9.1.1/KWZD-6V4
headEdward C Ferguson M 57 IL wifeIda F FergusonF 56 IL