(CNN) We've seen a flurry of recent activity in efforts to reunite migrant children removed from their parents.

But with all the legal and political wranglings, the latest developments can be difficult to follow. Here's a quick look at what's new and what's next:

What's the latest?

-- The US government hasn't been able to find the parents of 71 children who were likely separated from their families, a Health and Human Services official said Monday.

"There are some children who we believe are separated for whom we have not yet identified the parent," said Jonathan White, HHS assistant secretary for preparedness and response.