Kindred Can Die.
While Kindred is a "concept" aka death, he/she/it/them can still die, or at least not exist.
How?
*When all life in the universe dies. *
Why?
Because. Kindred is death. But without life, there is no death. It's that simple. You can't have something be something if its opposite isn't there. There is no good without bad, no bad without good, no kindness without cruelty, no cruelty without kindness, no honestly without lies, no lies without honesty, there is no life without death, and there is no death without life. Without a concept's opposite, it can't exist or be fathomed. It just is.
Likewise, if or when all life, in any and every form is gone, Kindred will be gone.