var bday = new Date(1989, 3, 13, 3, 0),
    ones = ['', 'one', 'two', 'three', 'four', 'five',
            'six', 'seven', 'eight', 'nine'],
    tens = ['', '', 'twenty', 'thirty'];

function calcAge() {
    var diff = (new Date() - bday) / 1000 / 60 / 60,
        year = Math.floor(diff / 24 / 365.25),
        year_tens = tens[Math.floor(year / 10)],
        year_ones = ones[year.toString().slice(1)],
        days = Math.floor((diff / 24) % 365.25),
        hours = Math.floor(diff % 24 % 365.25);
    $('#age-yr').html(year_tens + '-' + year_ones);
    $('#age-day').html(days);
    $('#age-hour').html(hours);
};

calcAge();
setInterval(calcAge, 5 * 60 * 1000);