So my wife and I went on vacation. We had another person watering our plants while we were gone.

We came back and started unpacking when my wife yelled, "Hun, there's something wrong with the Banana Tree!" (It's a Blood Banana.)

I walked out to where the tree is for the winter and it looked as if the tree was happy to see me. It's growing another tree out of it's base.

Now I know this is normal, but I don't know what to do with it. It's halted growth of the main tree. Can I just cut it off? Can I actually separate it from the main tree and plant it? I'd love to have a second tree.

What can I do?

You can either just cut it off or propagate it. Most suckers are either "sword suckers" bearing narrow sword like leaves or "water sucker", which are wide leaves. Sword suckers are the prime suckers to propagate. If it is not a sword sucker, I would not bother with it, just cut it off at ground level. You will get plenty of additional suckers in the future. Carefully dig down around the sucker. Make sure the sucker already has good, healthy roots. Clear the soil back as close as possible to the main rhizome and, using a clean sharp knife cut the sucker free, being careful not to break or pull off the roots. A sucker one foot tall with a leaf or two is ideal. Clean the cut surface and dust with a powdered fungicide or a bit of rooting hormone with fungicide already in it. Rest the cut sucker in shade for as long as a day or more to allow the cut surface to dry and heal before replanting. This new sucker is now ready to plant where you wish. (Bananas You Can Grow). - Millet