datepicker in windows application using csharp

Question

i am developing application using data grid view in c sharp.
 

Two fields as follows;
 
Start week date              End week date
(Datepicker)                     (Datepicker)
 

 
for example

  date picker1                           date picker2
Start Week Date                    End Week date
18th Monday choose             23rd Saturday  automatically display in the End Week date.
in date picker1
 

when i choose the 18th Monday in the date picker1    Start Week Date , in the end week date 23rd Saturday automatically want to display in the date picker 2.
 

and another condition in the datepicker 1  starting date always to be monday.if any date choose in the date picker want to show the message starting day always be monday.choose monday date only.


how to do. please help me.