A few weeks ago I had a text from my DSis saying 'Did I tell you that we are coming round for lunch on Saturday?', I replied no, asking her what she meant. She then responded with 'Shit, I told someone but I guess it wasn't you. We'll see you on Saturday.' DH and I have just moved house and we have a four month old so I was a little annoyed that she was trying to come round as she knows our house is a mess and we're knackered but her living situation is delicate. Her and her DP live with their child in his parents' home but his parents are very keen for them to leave. She agrees to arrive at 1pm.
DH and I prepare lunch to be served at 1pm and I'm texting my DSis about other stuff over the morning and she's responding. At 12:45pm I text and check where they are and she says they haven't left yet. So I asked her why she didn't tell me that they hadn't left at 11am (it's a two hour drive) like she said they would. She says her DP wouldn't get dressed. At this point my DH is annoyed and says tell them not to bother to come as he doesn't want to wait another two hours to eat lunch. I politely suggest that we rearrange as the food is done and won't be very nice once they arrive but she says they can't rearrange as her boyfriend will start an argument about it. I repeat that we are hungry and had they said they would be late we would have held off cooking. She reads the message and doesn't respond. They turn up at 3pm, without my nephew.
We eat and it's fine. I apologise for a certain part of the meal as it's slightly overdone. I attempted to reheat the food once they arrived and inevitably it dried the meat slightly. My DSis responds 'Don't worry this is why we don't let you cook Christmas dinner'. I couldn't believe it. I don't do many things well but food is my thing. I cook and host really well and despite my ugly flat I always have people asking to come round for dinner because I cook well. My DSis once made Christmas dinner and it was completely inedible and some of our guests refused to eat her cooking but no-one directly says these things to her. I replied that the food was perfectly fine to eat at 12pm and she doesn't respond.
At 6pm I tell my sister that my DD usually goes up to bed at 7pm and we go up with her as she's under six months. She asks if I'm trying to get rid of her and I say no but we need to get to bed, DH and I have been up since 5am. Her and her DP stay until 8pm.
She's now asking to come round again for lunch and has requested a specific menu. Can you help me phrase a polite response?