How do I combine a list of dates & a value into 1 week intervals
 

I would like to combine a list of random dates with a certain value next to
them into one week intervals. Some of the dates are repeated with different
values, or there are different dates within the same week all the different
date entries, so how do I sort and combine these dates and values so they are
in one week intervals with a date that starts Sunday of every week.