Fucking hell. What could go wrong there?
Nothing. Nothing will go wrong here.
The young trans boy will be easily accepted as a boy and man by every character whose opinion is framed as reasonable.
From time to time characters who have been written as prejudiced against other minority groups may find it difficult to accept the trans boy as male. This will be a learning opportunity for characters. ThE issues will be expressed superficially and framed as an expression of those characters' general small mindedness. Specific questions about comorbitities and the relationship between trans gender identities and gender stereotypes will not be mentioned. Resistence to genderism will be framed simplisticly as a general distaste for cross gender identities.
The older transwoman will embody selfless maternal concern. She will perform the Mrs Madrigal ideal transmom steteotype. Her gender will be portrayed as unproblematically female and utterly non-sexual.
In short, it's a made up situation with made up people who will behave exactly as the scriptwriters decide they should. They will portay the world the TRAs imagine not the world as it really is.
That's why this type of activism is so dangerous.
Case by case each instance can easily be minimised. "Seriously? It's just a TV show! God you GCs are so paranoid it's scary!". But in aggregate, all these constructed stories build up an impression about reality that is in fact based not on any actual reality but on deliberately constructed unreality.
Of course, I'm not suggesting this is a deliberate deception. The fantasy of hidden conspiracies is a thing of TRA paranoia not rational analysis.
What I'm suggesting is that because the scriptwriters are immersed in the "TWAW, most oppressed, women are not body parts" narrative, they truly believe their imaginary trans women character demonstrates the "truth" about trans women better than the many real world examples of trans women who do not embody this selfless feminine ideal. They truly believe the actions and statements of real world trans women are a red herring that should not form part of the conversation.
They believe the real truth is the world as they want it to be and that matters far more than what the world might currently be, because what the world might currently be is just something that happened to develop in the short term because no one was trying to make it better. So from that perspective, if reality currently contradicts our claims it's best to ignore it because while it might be real in the short-term that's just happenstance, it's not the truth!