The relative who borrowed the money runs a company—they apparently had cash flow issues, which is why they borrowed money.
It was due five months ago, but they haven't paid back a dime, so there was no choice but to have Old Song sue them.
Old Song had pretty much sorted out all the evidence; there was no promissory note, but there were chat records, transfer records, and everything had already been notarized.
In fact, for a civil loan lawsuit, these pieces of evidence are already enough.
Contrary to what many may think, evidence in civil cases is often not that complete, so as long as your evidence seems more convincing than the other party's, that's what matters.
The principle of high probability, for instance, what if someone borrowed your money and didn't pay you back, but you have no IOU, and the money was given in cash? What do you do then?
