Inspired by my family tree (credit for idea goes to the amazing Belphoebe!)
LN: one syllable, anglicized Irish
DH: first name is Southern and masculine, and his middle name starts with a Q, X, or Z.
DW: first name is a feminine spelling of a masculine name, middle name is filler. Her maiden name is two syllables.
DS1: First and middle names are common Biblical. Goes by middle name.
DS2: First name is literary and a common English name. Middle name is one-syllable. Also goes by middle name.
DS3: First name was common in the 70s, middle name is African-American and starts with an L.
DS4: First name is Spanish, middle name starts with an L and is feminine African-American.