My old sister has to put marriage on hold because of her heavy works.

因为繁重的工作，姐不得不暂缓一下她的婚姻问题。

youdao

When I was eight years old, my sister was three years old.

我八岁的时候，我妹妹三岁。

youdao

My little grandson is no trouble at all, but his 6-year-old sister is a handful.

我的小孙子一点不用人操心，但他6岁的姐姐却很难管教。

《柯林斯英汉双解大词典》

To be honest, I was feeling pretty negative myself until I heard that my 18-year-old niece and nephew and my 21-year-old sister have got summer jobs related to the Olympics.

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"There on the front page was a picture of my father carrying my ten-month old baby sister Jill out of the boat and behind him was her nanny being given a piggy back, " he said.

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Last week my 52-year-old sister died suddenly.

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