Complex sentence: His eldest is a son Tukaroto Mahuta (who has 4 son's and a grandson) his elder daughter, Nanaia, is a Labour MP (and has one son) and his youngest Tipa (whom has 1 daughter and a granddaughter).
Split into simpler sentences: His eldest is a son Tukaroto Mahuta (who has four sons and a grandson). His elder daughter, Nanaia, is a Labour MP (and has one son) and his younger daughter is Tipa (who has one daughter and a granddaughter).