javascript - fnPtr is not a function when adding element to array in AngularJS -

i'm having trouble.

i have checkbox, when checkbox checked want load 3 objects array, when happens see error occurs 6 times:

error: fnptr not function parser.prototype.functioncall/<@http://localhost:8383/myapp/js/angular.js:10568:15 operators["==="].... error: fnptr not function parser.prototype.functioncall/<@http://localhost:8383/myapp/js/angular.js:10568:15 operators[">"]....

what i'm doing wrong?

this code:

html:

     <div class="form-group col-sm-12 subject-field">            <label>has children?</label>            <input type="checkbox" ng-model="marriage.has_children" ng-change="setsons()" title="if had children check box">      </div>      <div class="col-sm-12 col-md-12" ng-repeat="littleboy in marriage.children">      <h3>{{$index+1}}</h3>      ...      </div> 

controller:

     angular.module('dexpress').controller('formcontroller',['$scope',                                                      '$filter',                                                      '$http', '$log',                                                      function($scope,                                                               $filter,                                                               $http, $log)     {          $scope.marriage = {                lives_togheter: false,                has_children: false,                celebration_date: $filter('date')(new date(), 'dd-mm-yyyy'),                separation_time: 0,                another_information: "",                state: "montevideo",                city: "montevideo",                country: "uruguay",                children: []          };            $scope.addson = function(){                var person = {                              name: "",                              surname: "",                              birth_date: $scope.today,                              studies: false,                              where_studies: "school...",                              year_of_study: "1st grade",                              is_disabled: false,                              explanation: ""                };                $scope.marriage.children.push(person);                             };          $scope.setsons = function(){                  if($scope.marriage.has_children){                      $scope.marriage.children=[];                      $scope.addson();                      $scope.addson();                  }else{                      $scope.marriage.children = [];                  }                 };       }