Next of Kin Walkthrough guide

Kill the remaining members of the Draconis family and wipe out their bloodline.

Get the Dead Drop Orders #2 from an Old Sack that's hidden in the Great Oak tree in Chorrol.

・Head to the Perennia Draconis' house in Applewatch.
・Kill Perennia and loot the Draconis Gift List.
・Kill Perennia's four children.
・Find the next Dead Drop.

These are the location of Perennia's four children:

・Andreas Draconis - Drunken Dragon Inn
・Caelia Draconis - Castle Leyawiin
・Matthias Draconis - Imperial City Talos Plaza District
・Sibylla Draconis - Muck Valley Cavern

If you want to avoid having a high bounty on your head, try provoking each one so they will attack you first. Or, you can simply assassinate, use a Frenzy spell, or poison them without anyone noticing.