Unusual Question re: Internet Connections

I have rather unusual situation that I am trying to assist someone with.  I was contacted by a lawyer who represents a child in foster care.  Both this child and a relative of his are quite ill and essentially immobile.  One is located in DC and the other in PA.  The lawyer is attempting to set up a situation where the two can speak while being able to see each other as well.  I figured a webcam is the best way to do this, using one of the many sites that offer such a service.  

This is where the problem enters--the lawyer is not sure of each party's computer/Internet situation, and was planning on bringing his own laptop to the site in DC.  I am also sure that the folks in PA can arrange to use a computer and a web cam as well.  My concern is more about the Internet connection (he is supposed to get back to me re: this), they most likely do not have a fast connection, or possibly not one at all.  Is there any way that one could gain temporary access to a good Internet connection from their respective homes without having to sign up for an actual long-term plan?  (I am envisioning something like a prepaid cell phone; although I have no idea if such a thing exists!)  

If anyone can offer any suggestions on how this may be pulled off, I would greatly appreciate it.  The story really tugged at my heartstrings and I can't bear the thought of two ill people not being able to say goodbye to one another.  Thank you in advance--Start Free Trial