Family members of a third-country citizen (the applicant) who plan to join them for a period longer than 90 days must apply for a temporary residence permit for family reunification purposes.
https://www.researchinslovakia.saia.sk/en/main/welcome/visa-and-entry-conditions/prijimanie-cudzincov/vstup-a-pobyt/rodina/prechodny-pobyt-zlucenie-rodiny