Interestingly (and now very off topic), she hasn't even seen Frozen. She does not yet know it is a film AFAIK, and I'm in no hurry to tell her.

I believe that the concept of Frozen has been explained to her by her peer group, through the medium of hair plaits.

Three year old kids are a weird and amazing bunch.

Thinking about it a little more, we've listened to a lot of Moana / Frozen / Disney on my Spotify account and none of that has come up in the Discover Weekly, so I guess they filter for it somehow already. Though I guess when they compare to other people with the same tracks you'll probably get a bunch of listeners that fall into a similar category anyway. Also, it doesn't sound like the number of times you play a track adds a huge amount of weight anyway.