Dear Dad,
How are you doing? I hope you are recovering fast from your illness and that you are already feeling better. I want to apologize for not being able to visit you at the hospital.
I was sent by my office to an international conference in London and I could not leave at the time I received news of your operation.
I am back home and have requested a leave of absence from work next week so that I may visit you there. I am really sorry I wasn't able to accompany you at the time you experienced extreme pain.
It is fortunate that Linda was able to fly home immediately and see you. I will make it up to you and cook you your favorite food when I get there. We will spend a great week together, doing what we have been doing when I was still a child.
See you soon, Dad.
Your son,
Jeffrey