User blog comment:Mich, Michele & Kuhla/Future Units Preview/@comment-26815065-20151003155438

For the new Bonded by Blood Set I figured this out so far

Avan-Vargas' Father

Rune-Cousins with Either Signas or Raydn (Probably Raydn)

Dolk-Predicesor of Zelban

Lagan-Zeln (both use Martial Arts)

Sharl-Havent figured that out yet

Chrom-Uncle of Elza

We'll see if I am close