Butting into a private conversation

Apathy Jack writes:

"Mele, who exactly is coming into school?"
"My cousins. They're coming to pick me up."
"How many of your cousins? How many of them can fit into one car?"
"They're walking."
"They're picking you up by walking?"
"Yes."
"I understand. You see, the thing is, when a large number of Tongan outsiders come into the school grounds, it makes us a bit nervous, so we ask them what they're doing here. The answer is always 'Oh we're here to pick up our cousin'. And when we ask them who their cousin is, they always say Mele, because every Tongan at this school is named Mele."
"Not all of them!"
"Alright, the boys are all named Sione, but you get where I'm going with this. Do you see why I'm worried?"
"Yes Sir."
"So your 'cousins' don't really need to 'pick you up'?"
"Yes they do."
"Right, let me fetch my to-do list, I have something that needs remembering..."