This is so cool! I just learned that I am still an Australian citizen and have had dual citizenship my whole life!
My mother was an Australian war bride and my father was a US serviceman stationed in Australia during WWII. At birth I became an American citizen through my father and an Australian citizen through my mother. My mother and I came to America when I was a baby. I was raised in the United States and didn’t return to Australia so I never thought that I might still have dual citizenship but I do. I can even get an Australian passport if I want to jump through those bureaucratic hurdles.
Does this change anything in my life? No, not really, but it feels very satisfying to reaffirm that part of my identity.