Is black and white, their your dp's children until you are married then they become your step-children, or do you become a step-parent when you move in together?
DP and I have been together since DS was 2, he's now 5 and we live together. DP is a huge part of ds's life, treats him as his own and they both love each other very much. Would DS be classed as his step-son only when we marry? And if we choose not to marry would he always just be his partners son?