Here's why the phrase uses "breadline":
* Bread is a staple food: It's essential for survival and a symbol of basic sustenance.
* Breadlines: During the Great Depression, people would line up for free bread handouts from charities. This imagery represents the desperation and hardship faced by the poor.
Other ways to describe the same situation:
* The family is living in poverty.
* The family is struggling financially.
* The family is experiencing economic hardship.
* The family is below the poverty line.
Remember that "on the breadline" is a figurative expression and doesn't necessarily mean a family is literally queuing for bread. It's a powerful metaphor to illustrate their financial struggles.