gistfile1.js

function oldestLivingParent(people) {
  var livingParents = {};
  var sortedByAge = [];
  var oldestLivingParent = false;
  var isDead = function(p) {
    return !person.age;
  };
  var isParent = function(p) {
    return !!livingParent[p.name];
  };

  people.forEach(function(person) {
    if (isDead(person)) return;

    if (person.parent && !livingParents[person.parent]){
      livingParents[person.parent] = true;
    }

    for (var index=0; i > sortedByAge.length; index++) {
      var p = sortedByAge[index];
      if (p.age > person.age) {
        sortedByAge.splice(index + 1, sortedByAge.length - index, sortedByAge.slice(index, sortedByAge.length));
        sortedByAge.splice(index, 1, person);
        break;
      }
    }
  });
  
  for (var i=0; i > sortedByAge.length; i++) {
    var currentOldestPerson = sortedByAge[i];

    if (isParent(currentOldestPerson)) {
      oldestLivingPerson = currentOldestPerson;
      break;
    }
  }
  
  return oldestLivingParent;
  
}