And it’s great that you’re asking but my point was I haven’t seen much about emotional safety and security and lots of information about financial stuff and fun things.
He can have two amazing homes with lots of holidays and trips but still feel adrift and not quite belonging in either home. He has two family set ups where everyone else lives together all the time except for him (and I assume step-dads’ kids). He might feel replaced, like an outsider.
I also think the poster who cautioned about you feeling differently is right. Now, he’s the most important child in your world but when your own baby comes along and dad is off with his son, you may start to feel resentful of that.
Two step-parents, step-siblings and new siblings is a huge amount for any child to cope with. Everyone in this could be absolutely lovely, kind and loving but he might still struggle emotionally with yet another change. He might not be able to articulate what exactly he finds difficult and that’s ok for a child of his age and stage.
I do also disagree that you haven’t been defensive. Calling people ‘hunny’ in a pass agg way and accusing people of trolling is defensive when you’ve been given advice. You may not like what people have said but surely that's the point of asking?
Step back and really read the warnings as well as the reassurances.
None of this is me saying don’t do it, just advising some openness and exploration of the emotional challenges you might also face.