I have a sister that is older than me, she owns a digital agency and I occasionally help them because they do not have employees for the stuff I do. We agreed on a hourly basis to get paid yet it's been 2 months with me not getting the cash. They keep delaying meeting with me and even when they do they 'forget' to bring cash with them etc.

Today I got a bit angry and asked "is that the way you pay other employees too?" To get her the hint that it's too much delaying, she replied "you don't feel any shame asking that?".. I get her saying that because I am yet transitioning from being the nice guy and she new me carying and helping since we were kids. The thing is that they helped me in the past too yet I thing things related to work and getting paid should be taken seriously because I could invest my time in other jobs that pay me on time. I know for a fact they have the money and don't necessarily experience hard times, is that they got too comfortable with me being nice. I plan to stop working with them if they will not pay me this weekend. Do you think I handle it correctly? I know it depends a lot on the level of connection between the family, we've been pretty close so far and generally no conflicts. Thx