"Bar Riddle" joke

Santa took a trip to Sydney, Australia. While in a bar, an Autralian on the next stool, spoke to our Santa in a friendly manner.
"Look," he said, "let's have a little game. I'll ask you a riddle. If you can answer it, I'll buy you a drink. If you can't then you buy me one. OK?"
"Yeah, that sounds pretty fair and exciting too," said Santa.
The Australian said, "My father and mother had one child. It wasn't my brother. It wasn't my sister. Who was it?"
Santa scratched his head and finally, when he was tired of thinking, said, "I give up. Who was it?"
"It was me," chortled the Australian.
So Santa paid for the drinks.
Back in Ludhiana Santa went into the bar and spotted Banta, "Hey Banta," he said, "I got a game. If you can answer a question, I'll buy you a drink. If you can't, you have to buy me one. Fair enough?"
"Fair enough," said Banta.
Ok...my parents had one child. It was not my brother. It was not my sister. Who was it?"
"Search me," said Banta. "I give up, who was it?"
"It was some Autralian, down in Sydney."