Unfortunately, neither literary talent nor imagination is hereditary.
Do keep in mind, from the article, Mr. Tolkien is reworking the story found in an older work by another author, and Mr. Dickens is reading it aloud for an audio book. By the way, while generally accurate, the generalization about some things not necessarily being hereditary, does occasionally run aground. When you get a chance, look up the mid-nineties work by a band called Bloodline, then note the names of some of the members. ;)
True indeed, but the audio book might be worth a listen.
Then again, it might not. :-)