At Half brother and sister related to other family? the asker appears to provide the actual first names of adopted and assumed (half) siblings.
The three people mentioned appear to be still alive. I think that this, along with the asker using what may be their own real name, may make those people identifiable.
For the moment I am going to redact them, so that any error will be on the side of safety.
With respect to the question on Main that triggered this Meta question, my concerns are not about the privacy of the question asker. I think that they should be free to waive that. They are about the privacy of the (half) siblings who we have no way to be certain are equally happy to privacy waived.
I also see no problem per se with a question that says 'Let's call them Bob and Sue' because that states that the names should be considered to be fictitious. However, I think we should also view such statements in context with anything else in or attached to a question that may identify a potentially living individual. For example, if I talk about my only brother in a question and say "let's call him Englebert" and then use my full real name as my username then I think I am being insufficiently respectful and protective of my brother's privacy.