The temple of the Rainbow Goddess is based in part on the temples I saw dedicated to Jizo during my trip to Japan. Below are some scans out of the photo albums I made once I returned (I took a ridiculous amount of photos on that trip…I think 10 rolls a week?)
My chicken-scratch hand-writing reads:
As stated before, Jizo acts as the guardian for dead children. Each small Jizo statue represents a dead child. These can include children who die early, infants that die at birth, miscarriages, and, recently, abortions. Often such statues will have red (the color of good fortune) knit caps on their heads and toys or food at their feet. These are essentially gifts to the child given by the mother, who after will pray for the child’s soul.
…Looking back, I’m not sure 16-year-old-me was completely accurate on that, but that summarizes what I was told by the people I was with.