In a tweet on Thursday, Joe Biden mourned the 6th migrant child who died in September while detained in U.S. custody:
"Over the last year, six children have tragically died in US custody at the border. It’s unacceptable. It’s not who we are. And silence is complicity. It’s on all of us to stand up and speak out. America is a nation of immigrants. We must guarantee everyone's treated with dignity."
The big picture: Biden and many other 2020 Democratic candidates have condemned the Trump administration's policies and handlings of the border crisis. Biden has consistently run on attacking Trump's divisive rhetoric on immigration and white supremacy.