What is Missing?

The last week has been pretty crazy. Unfortunately a lot of stuff for senior project and also a nice bought of sever stomach flu has made me less productive than I would like. However i have been making more progress in figuring everything out.I have been working on writing my opening scenes and have also started thinking about later in the script. I have come across a problem. The way I have it, the main character's grandfather, who turns out to be the main antagonist, disappears for a good amount of the second act. Basically, it means there is no visible character or opposition to my protagonist, and most of what he is involved in throughout the second act is his training and finding his niche in the circus and its magical performers. So I need to think of obstacles and other things to put into his way.