Nicely its not a kingdom Hence the title doesnt required Visit the eldest son but to the person they Believe is the Best for your title: brother , son , cousin ... but as an Emirati I assumed I could solution your dilemma about sending cards to Royals right here https://dubairoyalfamilymembers70123.blogsvirals.com/31998244/a-simple-key-for-royal-membership-card-unveiled