One of comics' greatest tropes is the use of the family. From despotic fathers to missing daughters, nothing can change a character like the bond formed by a blood tie. From the modern family aesthetic of the X-Men to the steadfast nuclear unit of the Fantastic Four, Marvel is filled with ultra-powerful legacies.
Many of the strongest familial ties come from siblings. Some brothers and sisters work hand in hand for the betterment of the world. Some are polar opposites, as far apart in personality as you can get. For others, it is a fine line between love and hate of which the boundaries are often blurred.
10 Cyclops & Havok
Scott and Alex Summers have always had a turbulent relationship. While they were children, their father's plane was involved in a crash. They both survived, but were orphaned and split up. Scott would go on to become Cyclops, leader of the X-Men, with Havok becoming the leader of the government-sponsored mutant team, X-Factor.
Their lineage would lead to a number of surprises as the years went on. Their father, presumed dead, was actually alive and traveling the galaxy as the space pirate Corsair. They would also discover that they had a younger brother named Gabriel, who would become a dangerous enemy of the X-Men.
9 Scarlet Witch & Quicksilver
In the pantheon of superhero siblings, it is hard to find a pair with a bond as strong as Wanda and Pietro Maximoff. First appearing as members of the Brotherhood of Evil Mutants, they followed Magneto. They would later find out that he was their father.
The pair would eventually become members of a new Avengers team led by Captain America. This squad would feature only previous adversaries. Redemption would be a theme that would stick with the siblings forever. Unfortunately, Wanda would later be responsible for the destruction of the team when she lost control of her powers.
8 Northstar & Aurora
Jean-Paul Beaubier and Jeanne Marie Beaubier were twins, separated at birth. Jeanne Marie was raised in a strict religious boarding school. In contrast, Jean-Paul was fostered, orphaned again, and spent his teenage years going off the rails. Despite very different upbringings, they shared a lot of similarities.
The two would reunite in the first incarnation of Alpha Flight. As characters, they have often been way ahead of their time. Jeanne Marie has often battled with mental health issues. Jean-Paul was the first LGBTQ superhero to feature in a mainstream Marvel comic.
7 Colossus & Magik
Piotr Rasputin first appeared in the milestone Giant-Sized X-Men #1. He was part of a new, international mutant team. As a gentle, caring Russian, he challenged Soviet stereotypes in a way seldom seen at the time. It stood to reason that the best way to develop this nature was to introduce members of his family.
Illyana Rasputin first appeared as a background character. She was later aged six years, developed the mutant power of teleportation, and trained in magic. While her brother, Piotr, has played the loving father figure, Magik (Illyana) has often been a cold, distant team member. Both of them share an older brother, Mikhail, who has been a recurring enemy of the X-Men.
6 Invisible Woman & The Human Torch
Family is what makes the Fantastic Four such a unique superhero team. The crux of this has always been Sue and Johnny Storm. Since their appearance in Fantastic Four #1, Johnny has always played the overexcited younger brother. Of course, every younger brother has to be put in line by their older sister once in a while.
This tension has often spilled over into the rest of the team, whoever is on the roster. Notably, the problems between Ben Grimm and Johnny have often been the real sibling feud, despite them having no blood ties. This adds to the Fantastic Four's appeal with the fans, showing that families come in all shapes and sizes.
5 Captain Britain & Psylocke
Sir James Braddock is a powerful being from a dimension known as the Otherworld. His children, Brian and Elizabeth "Betsy" Braddock, are just as powerful. When Brian was chosen to be Captain Britain his younger sister would soon manifest mutant telepathic powers.
While Brian would become a leader of the superhero team Excalibur, Betsy would join the X-Men as Psylocke. She would become a valued member, albeit one who prefers to work in the shadows. Her tenure with the team would see her body get swapped with a ninja assassin, and her eyes get replaced with television cameras by Mojo.
4 Thor & Loki
The accolade of the most famous sibling rivalry in comic history falls to Thor and Loki. One is the Asgardian God of Thunder, the other the God of mischief. Like true brothers, they are often at each other's throats one minute, then teaming up the next.
Like most sibling rivalries, their competitive nature stems from events set in motion by their parents. Loki was the child of a frost giant and was adopted by Odin, which has caused recurrent jealousy. It was Loki's meddling that brought Thor together with the team that would later be known as The Avengers.
3 Vision & Wonderman
For an android, Vision has an awful lot of family ties. Created by Ultron, he is essentially the son of the megalomaniac robot. In addition, he was created using the brain waves of Simon Williams, also known as Wonderman. While not biologically related, the pair have always believed this qualifies them to be brothers.
The pseudo-siblings have worked together throughout the history of the Avengers, and have helped each other out of many situations. Very often, these problems have involved their third "sibling," Avengers villain Grim Reaper. With the focus firmly on Vision in his upcoming Disney + series, we will see the MCU debut of his brother soon?
2 Professor X & Juggernaut
Professor Xavier does not have a fantastic track record with his siblings. His first, Cassandra Nova, was his twin sister whom he murdered in the womb. As he grew older, his only other sibling was a stepbrother, named Cain Marko.
Cain would bully Xavier relentlessly in their early days, as his biological father favored his stepson. Eventually, the two would serve in the Korean war. It would be here that Marko would find the Crimson Gem of Cytorrak and become Juggernaut. This made Marko one of the strongest beings in the universe. At times, he has stood alongside his stepbrother, the most powerful telepath in the universe. However, much of their history has been spent feuding.
1 Thanos & Starfox
Two of the more despicable siblings in the Marvel universe are Starfox and Thanos. Thanos' evil is apparent, as he is a galactic despot obsessed with bringing balance in the form of death. Starfox is the more sly of the siblings, who once even gained respect as an Avenger.
While Starfox opposes his brother's machinations, his motives are much more covert. He was once brought to trial by She-Hulk for using his powers of manipulation to seduce a married woman. He would later be suspected of doing the same to She-Hulk herself, and even go so far as to influence his own trial.