Omar:
Can you share the page or a screen shot? I am not completely sure what you are trying to do.
Can you also give an example of what you are expecting to see?
For example The code above will (based on your example) populate two date pickers.
datePicker1 will show a calendar with the only selectable dates being today and all the days up to a week from today (7 days).
datePicker2 will show a calendar with the only selectable dates two days after today and all the days up to 9 days from today (2 days + 7 days).
If that is not what you are expecting then you need to share more of your needs with a specific example.
I hope this makes sense.