The Bennets

The Bennets are an afluent upper-class familly about which the book Pride and Prejudice was mostly written.

Nuclear Family
(I'm only guessing at the age-order now)
 * Mr. Bennet
 * Mrs. Bennet
 * Jane Bennet
 * Elizabeth Bennet
 * Mary Bennet
 * Lydia Bennet
 * Kitty Bennet

Extended Family

 * Mr. Collins

Marries in
By the time Pride and prejudice ends, the protagonist is related, in one form or another to almost every character in the book.
 * Mr. Wickham marries Lydia Bennet
 * Mr. Bingley marries Jane Bennet
 * Mr. Darcy marries Elizabeth Bennet