Icy Veins/Putrid Bile question

I recently used a build that utilizes Icy Veins and Putrid Bile.

I thought I noticed that when I was abing, I used Icy Veins>Putrid Bile in that order, and only ONE of them triggered after my target died (I knew this because it was a MM mob). Several othertimes, I noticed the same thing happen with smaller groups. I'm not sure if I'm just not paying attention or they overwrite on eachother, cancel eachother out. Does this happen with these skills or am I imagining things?

Nevermind, I just tested it out in 'Isle of the Nameless' and they both trigger. >.<