A：Dad, you keep talking about family in New Zealand. Who are they?

B：Well, that's your uncle Bill, his wife and two of their daughters.

A：Is uncle Bill your brother?

B：No, your uncle Jack is my brother, Bill is my brother-in-law, your mom's brother.

A：So his two daughters are my cousins?

B：That's right, Sarah and Jane are both your cousins although they are step-sisters.

A：What are step-sisters?

B：Sarah is your uncle Bill's older daughter. When she was young, Bill's first wife, Sarah's mom died. Three years later Bill married again.

A：So uncle Bill's wife is Jane's mother but not Sarah's mother. Right?

B：Yes. She is Sarah's step-mother.

A：And when are they coming to visit us?

B：They want to travel to Europe next year, and will visit us at the same Ae.