[procaryote]

I don't really understand the problem in 1

in 2, looking at your article, from your first query it looks like person_relationship contains both (A,B) and (B,A) for all related people A and B; otherwise the left join won't work. If you also make people related to themselves and store (A,A) and (B,B) there your query becomes much simpler:

    SELECT other.id, other.name
    FROM person p
      JOIN person_relationship r ON r.from_person_id = p.id
      JOIN person other ON r.to_person_id = other.id
    WHERE p.family_id = @familyId;

[chuliomartinez]

Creative solution! Of course this creates more maintenance to ensure such records exist. I guess you kinda proved my point, you have to work around it.