I have found numerous questions around this subject using dates, but none
that match perfectly so I figured I'd ask the experts.

I have a column of names repeating each day (Column B) and a column of how
many samples were taken from that person on that day. (Column D) What I'm
trying to do is say, "Every row that column b equals, "John Smith", sum the
corresponding column d"

I can't figure out a way to do this using the IF or SUM statements. Any help
would be appreciated. Thank you.