The US House Committee on Appropriations just passed a resolution to grant citizenship to Charlie Gard, a British infant. Of course, the resolution is only part of a much larger bill that would need to be passed into law by Congress/the President.
However, recently there has been a lot of noise from the executive branch of the US Government proclaiming that it has power over immigration granted by the US Constitution, with regard to the various immigration bans the White House has attempted to enact.
Considering this, and understanding that immigration policies in a broad sense probably came from Congress in some form (as there is a lot of existing 'immigration law' on the books), does Congress have the authority to grant citizenship to an individual? Can Congress pass a law that applies to a single, specific individual (rather than an office or position held by an individual, such as the Office of the President of the United States)? Is there any precedent for either of these things?