Was the Ghost Real?

First of all, let me say that I loved Invisible Ghosts.  I thought it was beautiful and tragic and hopeful.  And the characters were so well developed.  I just saw a patron checking out this book tonight at work and I went on and on and on and on....I know she will love it, too.  I also encouraged her to read others by Robyn Schneider as I think she just gets better and better. 
The one thing I am wondering is, was the ghost of Logan real?  I don't know!  But it doesn't matter.  I think that since Jamie could see him, too, he probably was real, but then I don't know.  I just loved this book!  And I will be thinking about it and recommending it for a long time to come.