Family reunification is a recognized reason for immigration in many countries because of the presence of one or more family members in a certain country, therefore, enables the rest of the divided family or only specific members of the family to emigrate to that country as well.
Family reunification laws try to balance the right of a family to live together with the country's right to control immigration. How they balance and which members of the family can be reunited differ largely by country.
A subcategory of family reunification is marriage migration in which one spouse immigrates to the country of the other spouse. Marriage migration can take place before marriage and then falls under its own special category, or it can take place after marriage and then falls under family reunification laws. Some countries allow family reunification for unmarried partners if they can prove an ongoing intimate relationship that also lasted longer than a certain period of time.
In recent years, several minors went on hazardous journeys to apply for political asylum status and enable their families to join them. In some countries, applicants must be at least 18 and can only reunify with dependant children under 16 or partners, not with parents or siblings.