My ex only paid me half the monthly amount we have agreed this week as he is currently not working (whole other story!) Today he texted saying he wants to take our eldest DS to a show in London next week as a special treat, we do not live in London so cost of this would be in the region of £75. I am considering saying no as he owes me more than that and as he isn't working I can't see how he will be able to pay me anything more. He gave me no warning about the shortfall in what he paid me and assumes that I can somehow manage without it and then plans expensive trips, it just does not seem reasonable!!