Add-on "Replies to this post"

When I quote someone (I will randomly quote a post from this forum now)

I need an addon or script that will make the address bar show that the SSL on my site is still secure even when embedding an outside image.
I have a backlink to the quoted post in question.

But what about the forward way. What if there's a controversial issue with lots of replies and I want to find posts that replied to one particular statement?

Does such a plugin/addon exist?

If not, it shouldn't be too hard. The information is there:

[quote="DRE, post: 694041, member: 5483"]
So you just need an M:N table that's updated when the posting is created/modified where you left have the posting ID of this posting and right the quoted postings.

For the forward link you then just start a search on the right side of that posting and find this one (and others).