clpsmum I am very sorry to hear of your loss.
I lost my darling dad when I was about five months pregnant with my dd. It was a terrible shock and very sad.
I really think you need to come to terms with the death of your grandparents (gradually) and to find other ways to celebrate their lives and what they mean to you.
Why not spend these coming weeks compiling a scrap book to show your child when they are older.
Please try to come to terms with this bereavement and move on with your pregnancy and birth as normal. Perhaps some counselling or specifically bereavement counselling www.crusebereavementcare.org.uk/ may help.
I understand that you want to remember your grandparents in some special way, can I suggest something lovely may be to plant a tree in their memory, you can do this with a charity or other organisation. Have a look at www.carbonzerostore.com/?gclid=CP7XjLLYkaMCFdQB4wodVQwznA for info.
I am sure your grand parents will continue to be a warm and special memory in your life and maybe you could visit the tree with your baby.
Please do not think this is a flippant suggestion.
I really think for your own sake and your baby you should let your pregnancy continue as normal for the optimum health of the baby. I am sure you would not be allowed to do anything other than that but even if you could, it would not be what was good for you or the baby and I doubt your grandparents would want this.
Why not celebrate their special day with a meal out or something nice and then go on to enjoy the birth of your baby in peace.
All best wishes.