In avatar legacy, (which is basically a book of letters and momentos that Katara, Aang, Toph, and Sokka gave to Tenzin.) Katara writes a letter to Tenzin and in the letter she says the reason she fell in love with Aang is because she loved watching him grow from a carefree boy, into a wise powerful man. And that she loved his fun loving, determined, and caring personality. And that she never knew anyone as amazing as Aang. Zuko was not exactly fun loving...
