Sounds like your dad has his hands full and can use some extra help. Here are a couple of recommendations:
1) Contact the American Cancer Society at[phone number redacted] and they can tell you what options are in your area.
2) Often friends and neighbors will reach out asking them what they can do. You can use an online tool: http://www.lotsahelpinghands.com. They let you create an online calendar and people can sign up for specific tasks that need to get done - such as provide dinner, help with cleaning, stay with mom so dad can get a break.
I am sure others will weigh in, too. But I will suggest that you post this in the Questions section. You can do this by clicking on the "Ask Network" link on your logged in home page or the "Questions" link at the top of this page. When you post needs/questions using our question feature, we route your question to everyone in the network who might be able to help.
Good luck and please keep us posted.