Recursion pattern in javascript

recursion.js

CategorySchema.statics.getLineage = function (categoryId, flag, done) {
  var self = this;
  var count1 = 0;
  var count2 = 0;

  var recurse = function (id, results) {
    var deferred = Promise.defer();

    self.findById(id, function(error, category) {
      if (error) {
        deferred.reject();
      } else {
        if (!_.isEmpty(category.children)) {

          var iterator = function (child, next) {
            recurse(child, results)
            .then(function () {
              deferred.resolve();
            });
            next();
          };

          async.each(category.children, iterator, function (error) {
            if (error) {
              deferred.reject();
            }
          });
        } else {
          var interval = setInterval(function () {
            if (count2 < count1) {
              count2 = count1;
            } else {
              deferred.resolve();
              clearInterval(interval);
            }
          }, 100);

          count1++;

          if (flag) {
            results.push({"category": category._id});
          } else {
            results.push(category._id);
          }
        }
      }
    });

    return deferred.promise;
  };

  var latestGen = [];
  recurse(categoryId, latestGen)
  .then(function () {
    done(null, latestGen);
  })
  .catch(function (error) {
    done(error);
  });
};