Dendrobium with one stalk doing nothing

[Toni1968]

This was given to me by a friend and it was just the 3 stalks with no leaves. now almost a year later and it has bloomed 2 times. I am happy about it BUT, one of the stalks has still done NOTHING! Is there anything I can do? Do I leave it alone? I love the delicate white flowers though! Any suggestions? Is it healthy? Thanks for all the help everyone is so willing to give!