Nope, sorry, I am female, married to a male, and he has two kids from a previous relationship. They have joint custody. There are all the standard problems of the mother badmouthing both my husband and myself. It's cordial face-to-face for all of us, but we've heard many things repeated by the 5yo that are definitely less than polite. I know enough from my own experiences that when they're older they will definitely see that as the immature behavior that it is, and I'm not terribly worried about it.
But when my parents divorced, I was old enough to know that no stepparent was trying to "replace" anyone, and that the whole thing was normal and workable. The mother has repeatedly told my stepdaughter that she is "weird" for having a stepmother and that "ALL the other children in your school have married parents" which is, of course, ridiculous, and we tell her so, but just TRY telling a five-year-old that her mother is wrong about something.
I know in the long run she'll figure out that she's at the very least in a sizeable minority, if not the majority by then, and that in general she should turn out to be a decent person despite her mother's hatred (they're mixed-race, and the mother's also pretty upset about that too, disregarding her own obvious role in making them that way). But for the time being it makes it hard to relate to her.
My larger concern though is how she will deal with her eventual half-siblings, since my husband and I plan on having children too. If you were very close to your halfbrothers, then I have hope.