You were 3 when your cousin died, and your cousin was 14. You are now 11 years older than you were when your cousin died .If he was still alive, he would be older than you -- but he's not still alive.
Think of it this way: As the years go by, you will continue to get older with each passing year. But, your cousin is, and ALWAYS will, remain 14 for all eternity. . He's dead, and he can no longer age.. .