You need to make two models: User and Relationship. First, make the two models related (one-to-many relationship):

Model: User

public function relations()
{
    return $this->hasMany(Relation::class);
}

Model:Relationship

public function user()
{
    return $this->belongsTo(User::class);
}

Then in your relational model (remember to set this on your migrations too), you need to have four columns: user_one , user_two , type_one and type_two .

For example: user_one: father's user id / user_two: son's user id, type_one: father / type_two: son.

So be it.