Little is known of the youngest son; it is presumed that he died young.

对于最小的儿子一般所知甚少，据推测他已经夭亡。

《牛津词典》

"Can you break that?" he asked the youngest son.

“你能折断这个吗？ ”他问最小的儿子。

youdao

The youngest son, the 20-year-old, how old is he?

最小的那个儿子，20岁的，他多大了？

youdao

This is my son, Zachary, pretty young but this is not the youngest record of laughing.

这是我儿子Zachary，他很小,还有比他更小的小孩发出笑声。

耶鲁公开课 - 心理学导论课程节选

Ali Haider - the youngest son of the ex-prime minister - is contesting a seat in the Punjab provincial assembly.

BBC: Asia

That day, my cousin Rajesh, the youngest son of my middle uncle, downed his breakfast at breakneck speed and dashed outside.

NPR: In The Kitchen With Madhur Jaffrey

He was one of six kids and the youngest son, but the one who seemed to take care of everybody else.

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