Here are some of the families in the 1st and 2nd books.
“Horst, the son of Ostrec and the blacksmith of Carvahall, married a woman named Elain. They had...Ostrec family
“ The Holcomb Family Holcomb = Nelda | | Brom = Selena = Morzan | | | | Eragon MurtaghHolcomb Family
“The following is a family tree of some major characters. Alden┬? Cadoc┬? Holcomb┬Nelda...Family Tree
“The Waldgrave family were a family from Belatona. At some point, the Dauthdaert known as Niernen...Waldgrave family