It's evident from the latest Dragon Ball Super chapter that Goku looks a lot like his father, and that's because of Bardock.
For the most part, we know very little about Goku's paternal grandfather Bardock. Goku's father, Bardock, appeared in the 1990 film Dragon Ball Z: Bardock - Father of Goku and in the Jaco the Galactic Patrolman story, "Dragon Ball Minus: The Departure of the Fated Child," which showed how he came to send Goku to Earth. With this new look at Bardock, the Dragon Ball Super manga has given fans their greatest look yet, and he's basically Goku.
Frieza and the Saiyans conquer Planet Cereal in Dragon Ball Super Chapter 77. At first, the Saiyans show up as Great Apes. Bardock is one of them. Bardock appears to be doing very little in the battle. In the end, he finds Muesli and Granola hidden in a church, however. An attack by a Cerealian smashes the moon just as he's about to arrive, turning everyone into their regular forms. After killing everyone except for Muesli, Granola and a Namekian named Monaito, the Saiyans resume their slaughter.
Muesli and Granola are on the verge of being approached by Bardock. She attacks him in revenge, which sends Bardock back in time to visit his wife, Gine, sometime before. She chastises Bardock for being absent for so long, especially considering he missed the birth of his first child. According to Bardok's observation, "Oh my goodness! That explains why your stomach has returned to its original shape." The new child is given the name Kakarrot.
Bardock chooses to step in for Muesli and Granola after he recovers his memory. He brings them to Monaito in the hopes that he may be able to save their lives from being taken by the devil. Eventually, the action takes place in the current day, and everyone agrees that Bardock is in fact Goku's father. Indeed, as Vegeta puts it, you're descended from a line of sensitive souls.
It's very evident that Bardock and Goku share more than simply a physical resemblance. Although Bardock is less refined than Goku due to his background, they both have the same desire to serve others, even if Bardock is a bit rougher around the edges. There is one other striking similarity between the two: they are awful fathers. Other characters have called Goku out for neglecting his family in favor of training, which has earned him a terrible reputation as a father. For some reason, Gine lecturing Bardock about missing the birth of his baby sounds a lot like Goku lecturing Chi-Chi. As a result, Goku and Bardock share many similarities.
Viz Media will release Dragon Ball Super Chapter 78 in English on November 19th.