Nero Hated His Mother
According to one ancient historian, the mad Emperor Nero tried and failed several times to kill his mother Agrippina the Younger, each time trying to up the ante. First, he tried to poison her on several occasions, but she always took an antidote each time. Then, he constructed a machine that would collapse her bedroom ceiling on her while she slept, but she caught wind of the plot and escaped.
Finally, he—seriously—invented a collapsible boat that would drown her while she was on a pleasure cruise. AND YET SHE STILL SURVIVED.