Do eyes stay open after death?

I've heard they can fall open because of gravity that's why mortitions sew them shut.

When a person dies, all of their muscles relax. If the eyes are open at the moment of death, they will usually stay that way. Also, if someone had their eyes closed at the moment of death, they will tend to open a short time later due to the relaxation of the muscles that open and close the eyes. This isn't always the case, but for the majority of people, the eyes will be open. Morticians do not sew the eyes shut. The old fashioned way was to take some cotton and place it under the eyelids. This kept them shut and gave them shape, as the eyes tend to sink back into the sockets after death. The current method of keeping the eyes closed is to use what are called eye caps. They have little grippers on one side, and are smooth on the other. The grippers keep the lids closed.