This is how I see marriage

humans
- id
- forename
- surname
- birthdate

binary_marriages
- id
- partner_1_id (foreign key references column humans.id)
- partner_2_id (foreign key references column humans.id)
- marriage_date
- divorce_date (NULL if still married)

>>1
humans

>>14
struct human {

Both don't account for situations such as >>6's