Timeline

Pre-Story
Goku is sent to Earth to conquer it. Instead, he is raised on it peacefully by a Buddhist monk.

Goku impregnates Chi Chi. They part ways.

Dragon Ball Zero

Goku goes looking for Chi Chi in search of marriage after getting a text from her. He marries the wrong woman for a week having forgotten what she looks like, until he finds her and they marry. She has their four year old son, named Gohan.

Piccolo enters the scene. He and Goku fight, with the latter coming out the slight victor.

Janetto comes to Earth to check on the progress of Kakarot. Fighting ensues and she is far stronger than he is. He collects the Dragon Balls. He wishes for Janetto's temperament to calm before marrying her, to which they have Goten.

Vegeta comes to Earth to see why Jane had not reported back. He soundly beats Earth's warriors and vows to return in four years time.

Vegeta returns with four Saiyans on Goten's 4th birthday. Goku beats them all soundly with Shito-Ryu Karate and minimal help. Vegeta reports Earth as having been conquered and stays on the planet after having been spared.

The United Government begins looking into the tremors reported due to the Vegeta fight. They case the area and collect blood samples. They ask for help on television, looking to see if anyone can help them unravel the mystery. Several people knowledgeable about Saiyans turn their information over to the Government, at which point the Government uses robotics to target the house of extra-terrestrials. When Vegeta returns and learns of this, he blows San Diego off the face of the Earth, and threatens all of California next. The Government stands down.

Vegeta starts studying Western Boxing.

''Time skip. Goku has fallen into alcoholism and many of the Saiyans now live in the same building''

Gohan and Goten begin going to public school. Goten is shown to be the favorite as he gets all the latest school supplies whereas Gohan gets all of his brother's supplies from last year, often with his name still on it.

Vegeta has his first argument with Chi Chi. It begins an intense rivalry that looks like it will cost Chi Chi her life.

Goku starts teaching Gohan how to save human lives by using hay bales and swine. Several pigs die due to these lessons (namely catching people who are falling).

Todd, who introduces himself as the Saiyan Soul Collector, appears in the series.

''Time skip. Goku and Vegeta are capable of going SSJ, Goku learns how to fuse, and is given the Potara earrings by Todd''

Gohan starts dating Ashley. She is later killed in a car accident while driving to the pool party and Gohan reaches Super Saiyan 5, before passing out and being hospitalized due to the stress put onto his young body.

Androids 17 and 18 are set upon a populous city by Dr. Gero, a former U.G. robotics operative who worked on the assignment to take down the Saiyans earlier on. Though meeting the androids head on, it's a stalemate and the androids have unlimited stamina. The favors tip against them as a second 17 is released, and the two fuse, creating Super Android 17. When Goku and Vegeta resolve to using the Potara earrings, they are gaining ground until Seventeen uses a blade that he had forged to split the harmonic bond between the two, separating them. 18 is taken down during this timeframe and Seventeen kills Dr. Gero, while the two fuse to form Gogeta. Seventeen's stamina is beginning to wear thin in the fight, but it's now or never for Gogeta as he has a minute left on the fusion. Rather than fight, Gogeta tries to dissuade Seventeen from carrying on his dead master's orders. The fusion splits, and Seventeen can kill the exhausted Z-Team without worry. Rather than finishing them, he collects the still-living 18 and leaves the battlefield.

The mansion that the Saiyans live in, Seventeen and 18 decide to move into, much to the chagrin of their Saiyan occupants. Android 18 upgrades into a super android.

Dragon Ball X

Gohan (23) visits from college as Goten (19) is still living with Goku. Gohan has been dating Videl, the daughter of washed-up wrestler Mark Satan.

Goten begins dating Tiffany, whom is later granted invulnerability.

Gohan finds out that Videl is being abused by her father, several times sexually, and kills him in a fit of rage.

The United Government siccs two robots out on a city, to see what it would do to the Saiyan population. The Saiyans respond, and the robots are well-shielded. Repurposing their electronics, Goten gets one to fight the other. Seeing that they were now weakened, the Z-fighters destroy them with ki blasts. However, their self-destruct device goes off and the world is destroyed - Tiffany wishes the planet back, and all is well.

Tiffany is reluctantly going to move away. Insecure, Goten frames an innocent man as having shot her parents with superspeed, before killing the man himself. Without anywhere else to go, Tiffany stays with her grandparents.

Christmas time comes around. The Saiyans buy each other conventional gifts, while the androids buy each other computer parts.

Vegeta starts dating Cassidy. He is one of the only characters not living in the mansion. He then begins serial-dating women, including Bulma and having an affair with Chi Chi.

Gohan has the summer off, and chooses to live at Goku's, who is warmer to him now. Trunks and Gohan begin talking regularly. Trunks is sore that Goten spends all of his time with Tiffany.

Moving into a house with Tiffany, Goten gets greeted by Todd. Todd tells him that Tiffany is not satisfied in their relationship any longer and is looking to cheat. Despite Goten's best efforts, he cannot rekindle the spark between them, as he watches her invite both Gohan and Trunks into her house, to cheat on him. After a few months of this and losing his sparring partner as a friend, Goten lifts her immortality, brutalizes, and strangles her to death in a park's bathroom.

A similar situation occurs with Vegeta's daughter Bra, whom Vegeta reluctantly lets date Goten (except with Gohan only). Having been betrayed by these two, he waits for his time to strike back - the upcoming Tenkaichi Budokai.

The Tenkaichi Budokai occurs. Vegeta is introduced to martial arts, and Goten bests Trunks before winning a pyrrhic victory of SSJ face punches before going SSJ2 mid-battle.