There are numerous articles on the topic of migrant children in confinenment on the web and in the library databases. To find articles from library databases, enter your search terms in the search box on the libary home page and click on "search". On the left panel of your search screen, you will be able to filter your search by Resource Type such as Articles, Books, Book Chapters, etc. You can also limit your search by date.
Here are a few articles to get you started:
Children Cannot Parent Other Children - The Atlantic
Detention of Immigrant Children - Pediatrics (official Journal of the American Academy of Pediatrics)
Kids Describe the Fear of Separation at the Border - The Atlantic
Seeking Refuge in US, Children Fleeing Danger Are Expelled - U.S. News and World Report
Written Testimony: "Kinds in Cages: Inhumane Treatment at the Border" - Human Rights Watch