Cindy I second what darrel says get your dad hooked up with a gastro doctor to get a peg tube asap, my radiologist insisted that I get one before my treatment started, they said it is more complicated to put one in once treatment is started, I am glad I did because there was very little that I could eat while doing radiation. That being said I am getting my peg out tomorrow after 102 days but man did I need it and use it.Best of luck and be strong for your dad.
always lenny