Alethea Nibley

"Hiro's a genius, but what he really wants is to be like his inventor big brother, Tadashi-but one day, Tadashi vanishes while saving Hiro's life. The only thing left behind to console the grief-stricken Hiro is Tadashi's last invention, the health-care companion robot Baymax. But the friendship that grows between the gentle bot and the lonely boy is only the beginning of their adventure"--