i hope u can help me...

i need two date inputs with datepicker and the second must be after the first date choosen... thats no problem with my code...

but i've need a second rule:
after first choose the second date must be max the sunday in the same week than the first date.

thats my code now for the first rule:

2. $(function() {
3.     var dates = $("#holiday_from, #holiday_to").datepicker({
4. prevText: '<zurück', prevStatus: '',
5.         prevJumpText: '<<', prevJumpStatus: '',
6.         nextText: 'Vor>', nextStatus: '',
7.         nextJumpText: '>>', nextJumpStatus: '',
8.         currentText: 'heute', currentStatus: '',
9.         todayText: 'heute', todayStatus: '',
10.         clearText: '-', clearStatus: '',
11.         closeText: 'schließen', closeStatus: '',
12.         monthNames: ['Januar','Februar','März','April','Mai','Juni',
13.         'Juli','August','September','Oktober','November','Dezember'],
14.         monthNamesShort: ['Jan','Feb','Mär','Apr','Mai','Jun',
15.         'Jul','Aug','Sep','Okt','Nov','Dez'],
16.         dayNames: ['Sonntag','Montag','Dienstag','Mittwoch','Donnerstag','Freitag','Samstag'],
17.         dayNamesShort: ['So','Mo','Di','Mi','Do','Fr','Sa'],
18.         dayNamesMin: ['So','Mo','Di','Mi','Do','Fr','Sa'],
19.         dateFormat: 'yy-mm-dd',
20. showMonthAfterYear: false,
21. showOn: 'both',
22.         minDate: new Date(2016, 2 - 1, 2),
23. firstDay: 1,
24.         onSelect: function(selectedDate) {
25.             $("#target").load("website_to_load.html?value=" + document.getElementById("holiday_from").value);
26.             var option = this.id == "holiday_from" ? "minDate" : "maxDate",
27.             instance = $(this).data("datepicker"),
28.             date = $.datepicker.parseDate(
29.             instance.settings.dateFormat || $.datepicker._defaults.dateFormat, selectedDate, instance.settings);
30.             dates.not(this).datepicker("option", option, date);
31.         }
32.     });
33. });
    

I've tried a lot with maxDate for the second input put i didn't get it :(

i'm not so good in js so i hope u can help me with...

(sorry for my bad english - i hope u can understand me)