The origin of this custom has its roots in several sources. Survivors of a death in the family may not be emotionally able to handle the stress of visiting a burial site. After twelve months, grief has had time to subside and the family may be better able to deal with a graveside visit. Jewish monuments sometimes bear the name of the deceased in Hebrew followed by the father's name, also in Hebrew, while the mother's name is omitted. No mention was made of Sarah, the Wife of Abraham.
Symbols are a very important part of memorialization.
There are many symbols that represent Judaism and are suitable for use on Jewish memorials. The following symbols are most appropriate and meaningful. They have been used for centuries in Jewish cemeteries around the world. The seven-branch Menorah represented the seven days of the week. Seven is also a holy number.