We have a way to connect TV shows via relations and then mark them as part of same Franchise, or being a Sequel, etc..
It would be cool to add similar relation that can be done for actors. For example connecting two characters in Father - Daughter relationship or Grandfather - Grandson, or simply Cousin.
Perhaps having the most basic ones for starters would be enough, like: Sister, Brother, Father, Mother, Grandfather, Grandmother, Son, Daughter, Grandson, Granddaughter. Additionally Husband and Wife options could also be included.
Additionally some more indirect ones could be added too, like: Uncle, Aunt, Nephew, Cousin, etc..
Each of these relations is many-to-many since each can have many others of the same type (etc. mother can have 5 sons, but son can have two mothers, or five uncles or 10 cousins, etc.).
Such related character could appear in the same manner related TV shows appear on the side bar when you're watching some show they're connected to.
I was just watching an old Columbo episode where Jack Cassidy played the badguy, and to my surprise realised he's grandfather of Katie Cassidy who I've seen in Arrow series. Maybe it's just me who finds these things interesting, but I don't see the downside of having ability to connect actors similarly to how we connect TV shows.