When I passed driver's test, some eons ago, my father handed me a simple metal key ring with four keys on it. Two ignition keys and two trunk keys for the great shoe box-shaped Mercury cars the family owned. I must have smiled broadly because next he said, That doesn't mean you can just use these keys." Which was right of him to say, good parenting. We were in the little kitchen in Crestwood, Missouri, a room I haven't seen for maybe forty years.
I still have the key ring although the two Mercury cars and their keys are long gone. My office keys, house key, car key, bike lock key, and so forth are on the old key ring.
I keep it as a token from a happy memory, a milestone in a young person's life, not just getting a license but also being handed my own set of keys by my parents and seeing, if I'm not mistaken, pleasure in their faces at their eldest accomplishing one of life's necessary steps forward.
And it has come to seem like a simple metaphor of parenting. Your parents hand you the keys you need there at the start of life's travels, organized on a key ring, and later those keys fall away replaced by keys of your own choosing, but still organized on the ring they gave you as they helped you set out.