'Abdul Mateen (Malay: Duli Yang Teramat Mulia Paduka Seri Pengiran Muda Abdul Mateen; born 10 August 1991) is the tenth child and fourth son of Sultan Hassanal Bolkiah of Brunei by his former second wife, Puan Mariam binti Abdul Aziz, who is half Bruneian, a quarter Japanese and a quarter English.[1]