Have you ever been a step parent Lime?

Don't want to offend, but your post is a little offputting. The lady is not taking "someone else's kid" she's taking her step-son, who lives with her 50 percent of the time. It's not odd at all that she's willing to do it. And also, the child is 3, she doesn't need to be in the water with him.

No, I haven't ever been a step-parent, so maybe that is why I don't get it? I am sorry if my post was "offputting", whatever that means, I didn't mean to be. I won't bother trying to explain what I meant, just see Rogue's post below.
My apologies if my post upset you, it certainly was not my intent.

ETA: I was still required to be in the pool with my 3 year old, so his age isn't some magical beacon that makes my question irrelevant.

I think I read the first post differently to everyone else. I took it as she was concerned for the step mum because her husband is manipulative. I've got friends who are step parents and friends who are separated. And I know the parents would want to be a part of extra curricular activities, not to exclude the step parents. Not because they love the child more or anything horrible. And not expect the step parent to do it, it's not offensive to the step parents unless either parent is incapable. No one is suggesting that. I asked DH and he said that if it was him he wouldn't want her to do it so she could enjoy that special time. Not because she's an invalid. But because it's a special time. His second comment is he'd want to be at the lessons himself. If it were unavoidable sure. But in all the shared care situations we are privvy to unless it can't happen both parents prefer to be a part of these situations. It's not to be offensive, they are their parents. Why wouldn't they want to be there?