I am in the exact same situation. I have grandkids 2-3 days a week every week. When Jake(11 now) was a baby I kept him when the babysitter couldn't and then when he was 8 mos old she quit on them at 6 am in the morning! on a work day!
So I had Jake 6 days a week 10-12hrs a day. Those days were so special! It was hard to get up at 4 am for Jill to bring him but I did it. Sometimes he wouldn't go back to sleep and we would sit and watch Jay Jay the JetPlane til he went to sleep! Such memories for him and us! I had him til he was old enough for preschool and then had him 2 days a week. It was hard to not have him every day!!
The bond between Jake and me is very very strong! I highly recommend it if your health permits! It is such a special time!!
If Jake had his way he would be here all the time but circumstances don't permit it. I see him a weekend every other month and he stays for 2 weeks or more in the summer.
Now I have 6 under 12 and I have one or two or three every weekend. I love having my grands! They come and stay and we take them to the park and to MCDonald's etc!
Some of my favorite memories is of the twins when they were infants.I had two long plastic bins on my dining room table and lined them with blankets for cribs for them.
Enjoy this time and don't worry! As long as the baby is not crying nonstop for hours I'm sure everything is fine!!
Just a note-- I have found you can call a pharmacist and most of them will answer questions regarding colic and things that work. When I have had a question about how much of some thing like infant tylenol I call the pharmacist.
Something to keep in mind as a precaution
I never give a child anything medical without the parents permission.
When I had my daycare we were required to have a paper signed by the parent giving us permission to seek medical care in case of emergency. This is a good thing to have on hand even for your grandchild and should be updated from time to time!!
Tell Grandpa to relax and enjoy!! These days go by so fast!!