Using VFP9, how can I check for the occurrence of a part existing more than once in an order?

The following dataset contains part# 'part2' twice.

order# part#
1 part1
1 part2
1 part3
1 part2
2 part1
2 part2
etc....

I would like to see a query result that states 'part2' is found twice for order# 1. How can I do this?

Thanks,

Jerry