They discovered he had an illegitimate child.

他们发现他有一个私生子。

《柯林斯英汉双解大词典》

Rudeness is the illegitimate child of ignorance.

无礼是无知的私生子。

youdao

Illegitimate child. Old, denigrating, and now obsolete term for the child of an unmarried mother.

i私生子为老旧的、诋毁名誉的并且现今废止了的术语，意思是未婚母亲所生之子。

youdao

Nokia 6630 Charlie, the illegitimate child between the 6600 and 3660 was released and named the 6630.

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He was the illegitimate child of Joanne Schieble and Syrian Abdulfattah 'John' Jandali, 23-year-old students at the University of Wisconsin.

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He, on the other hand, had come from extreme poverty as the illegitimate child of an Irish immigrant, orphaned at 11, humiliated at school.

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