Hi Penny,
I'm the oldest sister of another threesome so I feel for you. Other than pointing out that you were the oldest, they were very good in describing you.
My husband was diagnosed in January right before our 25th wedding anniversary trip - which we had to cancel - and he had no risk factors or symptoms so the stage 4 was very hard to understand. That thrown for a loop feeling is pretty common and it does get better.
Since you are starting treatment, I guess I would say that focusing on symptom management is important. Side effects of radiation vary and didn't kick in for Jack until week 3 or 4, and some people on the forum have reported they have had minimal issues. Make sure you tell your doctors if you get any side effects.
Jack found that staying hydrated with 3 quarts of water per day and 2200 calories was a big help in preventing worse side effects. He used his feeding tube when it became difficult to swallow. Also taking strong anti-nausea drugs as a prevention on a daily basis - Jack used zofran with compazine for breakthrough - made the nausea very managable.
You will feel tired and will need people to help you. Please accept all the help you can. We organized our friends, family, and anyone who looked remotely interested to help drive Jack back and forth for the daily radiation/chemo, and for PT and speech appointments. People can help with shopping and child care if you need that, and this is one time when the house is not your priority.
Have someone with you when you go to the doctors appointments, and write out all your questions in advance so you remember to ask them. This site has some great postings on the getting through it project that you'll find down near the end of the patient forum. Scroll back and you'll find some good discussions. Also there is a great search engine on the home page that will give you tons of information. One that I remember is the article on statistics and staging because at some point you will come across numbers that will scare the hell out of you. It's good to have read that article to understand we are all individual and the numbers are averages, not people.
Don't forget about pain medication, and things like magic mouthwash for your throat when it starts to hurt down the road. Also, anxiety and depression can be big issues during this so don't hesitate to ask for medication, counseling and anything else that will help you get through this. Sounds like you could do a sister daughter day with your suportive family and that is just as important as the medications.
Tell people how you are feeling, do not keep it in and think you're being strong. Most of all, enjoy the good moments that you have and keep your sense of humor. This too shall pass.
Regards JoAnne