Be careful watering it!IT holds water in it's "trunk" I've had one for over 20 years,, Your is Beautiful, .. They like being rootbound,, When you transplant it try to keep most of the same soil with it and only go up 2-3 inches bigger in diameter and height! Even in the summer don't over water,,. I use 1/2
cactus soil and half potting soil and I use horticulture charcoal in the bottom of the pot,, You aunt may have pea gravel or something else at the bottom to use as drainage,
You sure have inherited some awesome plant!!!!!!!!!!