Carrie Underwood's first born, Isaiah, just turned 4-years-old and that's a big deal! Carrie Underwood took advantage of the Birthday balloons and gave a little twist to the 'Happy Birthday Song.' Mike Fisher shared the most adorable video of Carrie being 'Mom' a role that she knocks out of the park. After inhaling a big gasp of helium, Carrie sings "Happy Birthday" to Isaiah and WOW....when she broke down her son's name "Isa-iah-iah-iah-iah....." it'll leave you speechless. How does she do it? Even her helium voice is incredible! You could tell Isaiah loved the moment and then he quickly wanted to try it out and be just like his momma! Happy Birthday Isaiah!!!