This is a computer-based translation of the original text:
We have the bones of his father's burial tomb was designed by myself. Filial piety, so too late to have died, please give them a while I'm alive.
Original text:
自分がデザインした墓に
父親の骨を
納骨してきました。
死んでから親孝行しても遅いので、
生きてるうちにしてあげて下さいね。