They have two children aged six and nine.

他们有两个小孩，一个六岁，一个九岁。

《牛津词典》

They have two children together.

他们有两个小孩。

youdao

They have two children, Jim and Sue.

他们有两个孩子：吉姆和苏。

youdao

And she met her husband here, and now they have two children of their own.

WHITEHOUSE: Weekly Address: Growing Manufacturing with the Auto Industry Turnaround | The White House

Adrian is married to a fellow Five Live presenter, Jane Garvey and they have two children.

BBC: Match of the Day 2

She is married to Scott Cooper, a lobbyist for a nonprofit organization that monitors industry standards, and they have two children.

NEWYORKER: The Contrarian