Three people in a cabin on Triumph?

[flirtingwith50]

Need help figuring out how to tell which inside cabins can sleep three people. When i do a mock booking it gives me the rate for 3 people but description of cabin only has two beds. Would it give a rate for three people if there weren't 3 beds? I'm not sure which cabins have two beds and an upper, I can't find any that lists that in the description when i select the cabin. I see OV cabins that have the upper, but don't really want on a lower deck. Any help would be appreciated.