Something

 alias bday {
  var %b = $1-
  var %r = $calc($ctime(%b) - $ctime)
  var %o = $+($round($calc(%r /60 /60 /24 /30 /12),2),-Years $calc(%r /60 /60 /24 /30),-Months $calc(%r /60 /60 /24),-Days $calc(%r /60 /60),-Hours $calc(%r /60),-Minutes %r,-Seconds)
  return %o
}