Answer :
The mother's language revealed that her mother tongue which is her first language is interfering with her choice of words.
The mother meant to express that it is her daughter that will make the family's name popular.
What is an idiom?
An idiom is said to represent an expression that has different literal meaning to the group of words used.
For example, the following expressions are idioms which are used to add texture to grammar :
"I found myself being in a hot soup after falling from the stairs". This doesn't mean that I am in a hot soup. it means that I found myself in great pain after a fall I had at the stairs.
From the passage, Yoyo's mum must have lacked the ability to make proper choice of words in English language maybe due to her level of education. That was why she said 'headlight' instead of 'in lights'.
It could also be an interference from her mother tongue which is there native or original language.
Learn more about idioms here:
https://brainly.com/question/17515105
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