I know this post is old but did your symptoms ever get better or did you ever find out what is causing this both in you and in your Dad?
I've been having this for years too and suspect I may have Crohn's disease. you should see a GI doctor and get some tests and a colonoscopy. I still don't know if it is hemmarhoids or what, but I feel that I'm not normal since this has been happening for like 15 years and the pain is getting worse in my rectum
I think prednisone helps me but you can't take it long term and I heard it can damage the liver- I would avoid prednisone if you can
Let us know how you are doing and what you found out.