In The Crown's "Favourites" (S04E04) Prince Philip tells The Queen that she has an obvious favourite child, and she sets on a quest to figure it out.
She has lunch with each of their children, and she seems to be disappointed with each one of them for various reasons. I was hoping they at least hint at a solution, my guess while watching was that at the end Philip will reveal it's the horses (she is portrayed as an avid horse breeder), or that he will tell her it's the state (she mentions that she is a mother to Britain).
Clearly, the show is trying to not step on any unnecessary toes here. But maybe I missed something? Was there anything subtle, or was it a deliberate choice, leaving the audience to interpret, as did I?