My niece lives in the same town and turned 18 in April we don’t see a lot of her and never really have as my sister and I are totally different people (her words not mine) but we are. She has only ever wanted money for Christmas and birthdays since she was aged about 8 and does send a very short thank you text.
Their is a sixteen months age gap between my niece and my eldest DS and almost 2 1/5 years between my niece and DD. Niece has always been awkward with my two always playing one off against the other and when they were little she took turns winding one of them up and had them in tears every time she saw them. When they finally wised up to her she looked down her nose at them. If my children and myself went to my mums my niece was almost always there, always holding court, interrupting or tutting if anyone else tried to speak etc. When younger she would sit on my mums knee and demand a cuddle or want me mum to get her a drink, a toy or put her a video on to distract her from my two. Latterly she just ignores me or them, scowls at us or tries to talk over us etc.
Would I be unreasonable to stop buying her a Christmas present (money) now altogether and still buy her sister age 10 (who also now only wants money) or should I continue on with it for life or until 21?