HelpGuide.org reports that it's important to remember that everyone grieves on their own time - don't feel pressured to immediately overcome your feelings of sadness once your grandparent passes away. Because he or she was a big part of your life, it's crucial to step back and come to terms with the death before continuing onward.
When communicating with other family members during this difficult time, you may want to try to focus on the good memories you have of your loved one. Reminiscing together can help you grieve and support each other along the way.
Once you've come to accept the death, you might want to consider speaking to a clairvoyant to contact your loved one on the other side. A psychic reading can provide you and your family members with any additional closure you're seeking, and it can also let you know that your grandparent is okay.