Why Does My Brother Only Call When He Needs Something?
People are wired to spend social effort exactly where they expect a return, and nowhere else. Family calls only when they need something because of: 1) intermittent reinforcement, you have paid out often enough that asking is still his best bet 2) the reciprocity norm running one direction, he counts being blood as the thing he already gave you 3) hyperbolic discounting, a favor today beats a relationship later every single time. You are not his brother on those calls. You are his backup plan.
What is actually happening
The ask arrives before the hello
You say yes, the pattern pays
Silence returns until the next shortage
Blood becomes an invoice he never pays
How the cycle runs
Say no once and you find out which one of you was related to a wallet.