Hi

Welcome to the forum though sorry for the reason that brings you here.  You will find there are many who post and no one passes jusgement here but it just offers somewhere to offload and share your fears and support.

Your brother has the right idea I think.  No matter what the reason behind your two year separation from family, being there now is an important  part of support.  Whilst you may not be able to be there all the time your Dad and your Mum will appreciate you being back in touch and even at the end of a phone can mean the world to them.  It is very hard when we lose a parent (9 years since I lost my Dad to cancer) so take every day as it comes, welcome the contact you now have and if you can, say all the things you want to say.  As to how to help I think you have taken the biggest step by being there now but I found the best way was to ask my Mum what she needed from me and was guided by her and the medical carers.

I lived over 30 miles away from my parents at the time of my Dad's illness and had family of my own to look after plus a job at the time but phoned regularly and visited when I was able.  My parents understood.

Be kind to yourself and tuck the guilt away as it resolves nothing and spend what time you can with your Dad letting him know your inner feelings and bring him up to date with your life.  Upsetting it will continue to be for some time but make good memories whilst you can. Regards  Jules54