This article is from the ER FAQ, by Rose Cooper firstname.lastname@example.org with numerous contributions by others.
At a time before the first episode took place, Carol and Doug
were involved in a relationship that lasted for two years.
It is known that the relationship ended partially, but
possibly not completely, due to Doug`s habits of drinking and
During the first season, Doug tried to win Carol back, but by
that point, she was engaged to be married to John Taglieri. In "ER
Confidential" , Carol reveals to Tag that she slept with Doug in
a moment of weakness after she had started seeing Tag (at a time
before the series began). Carol and Doug shared an unexpected kiss
in "Another Perfect Day" . Also, during another brief period of
vulnerability, after her adoption of a little Russian girl with AIDS
was rejected, Carol tried to kiss Doug, but he gently declined her
advance ("Sleepless in Chicago" ).
After Carol broke up with Tag at the end of S1 ("Everything Old Is
New Again" ), she hooked up with Raymond "Shep" Shepard, an
EMT/Paramedic that she got along famously with. Until he went bonkers over
what he saw as his contribution to crispy-crittering his partner Raul ("The
Healers" ). Things went rapidly downhill, she showed him The Hand,
and he left...
...so anyway, after Carol broke up with Tag at the end of S1, and Shep
in S2, both she and Doug appeared to be over each other, and their
relationship matured into a healthy, supportive friendship...
...which, at the end of the third season ("One More For The Road"
), evolved into a deeper relationship. It remains to be seen whether it
will stay "healthy" and "supportive", though it appears to be, at least much
more so than the first go-round. In "Ground Zero"  and later, "Fathers
and Sons" , they expressed feelings of love for each other...
...which, in "Do You See What I See?" , led to a proposal of
sorts. Uh, of marriage. I think. Paramedics have come and gone, but
they're still hanging on. By a thread? Hmmm...
And we won't even mention the "She's Having My Baby" season five arc.
[Nope, won't mention it at all. Nosirree, not one little peep. Won't hear
a thing from me about it. Nuh uh. Not a thing. My lips are sealed.]
[Tune in tomorrow for another edition of, "As The Bedpan Turns"...]