Character relationships can make or break a story. Some key character relationships are:

 Mentor-Student

Paternal or Maternal (parents)

Love interests/lovers

Friendships

Enemies/Antagonizers

When creating characters in a story your relationships will determine the entire outcome. If you do not have an antagonist ("bad guy") then you likely have little conflict in the story. Your antagonist does not always have to be a bad guy, but can simply be an opposing force. For example, the maternal figure for your character can be an antagonist if she does not agree with the character and this propels your plot forward.

Following the writing theory of the hero (Found in Joseph Campbell's "The Hero With a Thousand Faces"), we see that every story follows a plot pattern and must have the mentor-student relationship. This mentor can be someone the hero knows before OR after the "fall of the hero". Essentially, as the hero goes on this journey, they will eventually fail. After this failure, their mentor helps them and they gear up to face the conflict once more and succeed. The mentor figure can be a person, thought, or emotion. In most cases, it is someone they are fighting for or someone who teaches them to fight on against whatever conflict they are facing.

The protagonist needs to follow this pattern to effectively grow and pose realistic challenges. A popular example to explain the Hero's Journey is Harry Potter. I have taken the following from a website : https://theweeklycauldron.weebly.com/a-heros-journey.html 

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HARRY POTTER AND THE SORCERER'S STONE: HERO'S JOURNEY

Stage One: The Departure


1. The Call to Adventure

Harry leaves behind his life with his vicious aunt, uncle, and cousin in the Muggle World when he receives and reads the letter from Hogwarts School of Witchcraft and Wizardry asking him to enter the magical world on his 11th birthday.

2. Refusal of the Call

"'Hagrid,' he [Harry] said quietly, 'I think you must have made a mistake. I don't think I can be a wizard.'" (58) -From Harry Potter and the Scorcerer's Stone, J.K. Rowling

3. Supernatural Aid/Advice from a Mentor
Harry has a number of friends and mentors who guide him along his journey. The most prominent among these are Dumbledore, Hagrid, Ron, and Hermione. Hagrid helps Harry begin his journey and introduces him to the magical world, assisting him throughout the course of the story.

4. The Crossing of the Threshold

Harry must leave behind the Muggle World to enter the wizarding world. He crosses The Leaky Cauldron threshold with Hagrid and crosses the barrier to Platform 9 3/4 with the Weasleys.

5. The Belly of the Whale

The final separation of the hero from his known world - Harry appears ready to transform and willingly enters with the help of the Weasley family.

Stage Two: The Initiation


1. The Path of Trials

Once Harry enters the magical world of Hogwarts, he is faced with a series of challenges that test the strength of his character and ability. Some of the obstacles that he encounters include 'The Sorting,' performing magic, and making friends. Other more prominent trials Harry must overcome are Professor Quirrel's various antics in attempting to harm Harry, Fluffy, the three-headed dog guarding the trap door to the Sorcerer's Stone, and the chessboard.

2. The Temptation

Temptations that Harry faces include joining Slytherin House, flying, and pursuing the Mirror of Erised.

3. The Ultimate Boon

The rewards at the end of Harry's journey include the defeat of Voldemort, the protection of the Sorcerer's Stone, and the house cup victory.

Stage Three: The Return

1. Refusal of the Return

Harry does not want to leave Hogwarts because he does not want to return to the Dursleys and because he feels at home at Hogwarts.

2. The Magic Flight

Harry Potter returns to the Muggle World on the Hogwarts Express.

3. Crossing the Return Threshold

Harry travels through the entrance to Platform 9 3/4 and leaves the wizarding world to return to the Muggle World. Seeing the Dursleys marks his return to normal life.

4. Master of the Two Worlds

After completing his first year in the magical world, Harry has conquered life in the Muggle World and the wizarding world. He changes as a person and becomes a hero.

END OF ARTICLE

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Understanding the Hero's Journey and how relationships affect the hero is important for effective character and world-building. You must have some kind of goal for the hero to accomplish, even if it is not clear in the beginning. 

Comment below if you have a request for this series! I'd love to help you in your writing in any way I can. I'm by no means a professional, but I like to think I give decent advice! :)