Which is the best relationship in this world?

Which is the best relationship in this world?Each one can give you a hundred examples and support his answer and each time the answer might seem to be true. Because you have chosen a subjective term to ask your answer 'best'. Anything for that matter can be good, better or best. Husband-wife, brother-sister, father-daughter etc. all these can be best and worst in their own ways and not all can