I opened youtube to find Portugal national anthem in instrumental version, and then I found a video which a little boy played the anthem with piano. His name Arjun Ayyangar. I could only say: WOW! And I saw the suggestions video in the right bar and there were many other national anthems played by him. He can play Indonesia Raya, too!
After I googled his name, I learned that he knows to play all national anthems of all recognized countries in United Nations. There are 176 countries! Amazing. The biography in his web said: "At age 2 he was proficient in reading and could read headlines from magazine articles. He could identify all countries on the globe and their flags and name their capitals. Arjun could name all the US presidents, identify the states on the US map and name their capitals, as well." Envyyy... hahaha...
He is gifted with perfect pitch and natural instinct of music. He can identify and hear musics and play it from 'ear'. I added here his video playing Indonesia Raya:
I felt touched. T_T