When I think of the phrase Daily Summary, I think of an email that
would contain all activity for one list or library that happened in the
past 24 hrs.

However, our users are receiving multiple emails that make up the daily
summary alert. I have daily summaries setup on one library. It is
setup to send an alert for items that are modified. Based on that I
should have only received 1 email, but instead I received 2. Both sent
at the same time. First one had 4 items and the second had 1 item
(Different items).

Does anybody know why this is happening or where I need to change
something?