In Judaism, there are several occasions each year when the dead are memorialized. The most significant of these is yahrzeit, the anniversary of the death, which is observed according to the Hebrew calendar. Most synagogues keep registries of the Hebrew dates of members’ deaths and send out notices reminding family members of the yahrzeit date.
As is the case in all Jewish holidays, yahrzeit observance begins at night. A 24-hour candle is lit and, as one woman I know says: “The spirit of the dead person fills the room again for 24 hours.” One attends synagogue for the evening, morning, and afternoon services and again recites the Kaddish [the memorial prayer].
One should not go to a celebration or party on the day of yahrzeit, and some people fast on that day.
The yahrzeit candle is lit during the week of Shiva (mourning). It is also lit at sundown on the eve of the yahrzeit (anniversary of the death) and at sundown preceding the start of Yom Kippur and at sundown preceding the last day of Succot, Passover and Shavuot.
These holidays all have yizkor (memorial) in synagogue as well.
Rest in peace, Dearest Alice.