In D&D 5e, a bard can give Bardic Inspiration - a d6-d12, depending on the level of the bard - which can be used by the recipient to add to a single ability check, attack roll, or saving throw within 10 minutes of getting the Bardic Inspiration die.
What happens to this Bardic Inspiration die when the bard goes unconscious/dies, or the character who received the inspiration goes unconscious?