[dirtyroboto]

There is also the Obon and Ohigan festival. These are the only times it is belived that the dead can eat.
At these times, many Japanese place food and drink infont of their home shrines in the hope that their starving lost ones can enjoy, once again, the foods from their life.

Having a shrine in a Japanese house is a good way for the Japanese family to always be reminded of the ones who came before, that helped them to be alive now. Many of these shrines are handed down over many generations and can contain many ancestors.

A tattoo will only ever exist on your skin and be lost on your death. If you are getting it for yourself then fine. If it is for your sister, then I would think she would have told you not to get it. You would only be changing the way she saw you, before she became a buddha.