The fact that Joseph looked familiar to them
The fact that they had been seated in order from oldest to youngest
The fact that they had stopped feeling scared of Joseph
Reuben, the only one who tried to get his brothers not to kill Jospeh
Judah, the one who had the idea to sell him to the Ishmaelites/Midianites
Benjamin, the youngest son who had the same mother as Joseph.
Until Benjamin had managed to eat every bite of the 5 helpings he had received
Until they became sick
Until they became drunk
No, he gave them all the same thing
Yes, he gave Benjamin 5 times as many clothes and money
The bible doesn't tell us
Go straight home and don't fight along the way
Don't pick up any hitchhikers along the way
Don't drink and drive
Here's an interesting quiz for you.