A bit of a vent really - it's just a little thing, but really does illustrate how step-family life can never function in isolation from other households 
DP has been away for a few days, and the usual contact arrangements with DSS have been changed. (there's another thread about that, and it's not the issue now).
It has been arranged that we would pick DSS up from his mums on the way home from picking DP up from the station later this evening. We have planned a family treat to get take-out for all of us on the way home - fairly normal family stuff but a really big treat for us as a family because we do it only once or twice a year.
DP had told DSS mum this when he arranged the pick-up, and she agreed that DSS could eat dinner with us after we'd picked him up; she would give him a snack after school to keep the hunger-pains at bay.
DP is on his way home by train, and has just texted me to ask if I still want take-out because DSS has had dinner at his mums 
. My DD has been looking forward to it too - and now we've either got change our plans, or risk DSS being left out while the rest of us choose and eat take-out. We'll let him share something, obviously, but it's not the same, really (and as he is currently keeping a food diary for medical reasons, it makes things even more complicated!)
Our plans for an enjoyable, relaxing evening have turned into something quite different because DSS mum decided to do something that in her eyes was very simple and probably of very little significance. All she did was give DSS dinner, after agreeing not to, but it has a huge impact on our household!