[reduce] {sb} to tears

to cause someone to cry or become emotional to a significant degree

The exact origin of the phrase "reduce someone to tears" is difficult to pinpoint, as it has been in use for a considerable period of time in the English language. This idiom is used in a variety of contexts to describe situations where someone becomes overwhelmed with emotions, leading them to cry. It is often employed when discussing deeply moving or emotional experiences, such as heartwarming moments, profound sadness, extreme frustration, or overwhelming disappointment.

The devastating news of the accident brought the entire family to tears, as they struggled to come to terms with the tragedy.
The harsh criticism from her mentor during the performance reduced the young actress to tears of humiliation.
The heartfelt eulogy delivered at the funeral reduced everyone in attendance to tears as they mourned the loss of a beloved friend.
The heartwarming reunion between the long-lost siblings reduced them to tears of joy.
The overwhelming gratitude expressed by the community for his selfless act of heroism brought the modest firefighter to tears of appreciation.