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Grandpa Son Gohan (孫 悟飯 じいちゃん, Son Gohan Jīsan; FUNimation "Grandpa Gohan", Viz "Son Gohan") is a fictional character in the Dragon Ball series created by Akira Toriyama. Grandpa Son Gohan is also the adoptive Human grandfather of Son Goku. He is often referred to as "Grandpa Son Gohan" to separate him from Goku's son, Son Gohan; who is named after him in honour of him.
Biography
Grandpa Son Gohan was a very loving and caring man who became the adoptive grandfather of Son Goku when he found him in a crashed spaceship when he was a baby. When Son Goku first landed on Earth, his mission was to, in time, destroy the entire human race and sell the planet to another race. Being a Saiyan, who are known to be very aggressive and short-tempered, Son Goku was very uncooperative at first (in the Bardock special, he simply laughs as Grandpa Son Gohan found him in the wilderness). But after falling into a ravine, Son Goku hit his head, causing him to lose his memory, and became a regular happy, loving boy. Grandpa Son Gohan was taught martial arts by Master Roshi and passed on his knowledge to Son Goku. Grandpa Son Gohan always warned Son Goku to never look at the full moon and to stay indoors on nights of one – implying that he had already transformed before and Grandpa Son Gohan managed to survive the first time. He followed his advice for sometime until one night when Son Goku stepped outside to relieve himself. He then glanced at the full moon, transforming into a Great Ape, and went on a rampage, killing Grandpa Son Gohan, though because Son Goku didn't remember what he did. From that time on, Son Goku believed that Grandpa Son Gohan was killed by a monster and that his soul was in the Four-Star Ball. In Dragon Ball Z, when Son Goku was battling Prince Vegeta as he transformed into a Great Ape, Son Goku finally realized that he had killed Grandpa Son Gohan when he was little.