Have one DS of my own whose dad is not involved at all. DP has 2 DSC with us half the time. We all get on well and we are planning on marrying.
Something that has been bothering me recently: My DS6 absolutely adores DSC. He constantly asks when they are coming, what they will do ect. He has started referring to DSC as step-siblings. DSC8 tells him off for doing this and says "I am not your step brother, I will never be your step brother" ect. They generally get on well aside from typical bickering.
Is DSC being reasonable (for an 8y/o) asserting his boundaries, or is this an issue?