SIL (brothers wife) and I do not have the best relationship for countless reasons which I can specify if necessary. However we are always civil and polite and that is sufficient. She constantly gets my brother to contact me to ask where I have got x, y and z from or who did I use for x, y and z. Examples being where we bought our fireplace which she now has in her living room, who did my hair for a wedding we recently attended and she has now booked the same hair stylist for her own upcoming event. She does this with countless things and has never once thanked me or even acknowledged that she has copied me. My brother will simply text me asking about said thing, I will provide the info and she will go out and copy. And it takes me a very long time to research and find these items/suppliers.
My daughters birthday is round the corner and I am planning to have someone come in to do some nice themed decor, a nice cake and a local chef will be providing me with the food, I just have to cook it. I just know that I am going to be asked either there and then or via text from my brother not long after who did x, y and z for the party so that they can use the same people. AIBU to not want to share this information and perhaps even lie about who I’ve used and claim some old friends helped me out as a one off but aren’t doing it as a business?