Dance songs should always have a personal meaning and the words should be studied carefully. I think it awesome that you are dancing with your brother and I hope you find a great song. One song that comes to mind is "Wind Beneath My Wings" by Celine Deon or possibly "Lean On Me" by Bill Withers.
it should be rocking and simple,at the same time to that particular occasion it should prefer rocking music.that time we can do nice steps top follow up that dance.nice rocking sings in many languages.