I need help with a manga im writing. PLEASE HELP?!!?!?!?!!?

The magical eye can be something that people were searching 1,000 years for and his older brother tries getting it but his parents try to protect the younger brother and, by doing so, end up getting killed by the older brother. However, the older brother must recover from the damage that his parents left on him and dissapears(but he is not dead yet). The reason he still likes his brother is because he doesn't remember anything from that day.