"creator = parent": not 100% definitive yet, but probably
"same creator of object show = sibling": almost. if THey are part of THe same show (e.g. battle for grandma, 5sos and bean's show), THey are siblings
but if THey are different canons entirely (e.g. object fool and ggg), THey are still related, but not siblings.
"creator's friend = parent's sibling": no