My name is Pumbaa!

We adopted this cat 4 years ago because we thought it would be a good addition to our family and because our other cat was by himself when we were at work or busy doing other stuff. He is originally from Minnesota (so he is very well adapted to cold weather), then we moved to Atlanta about 6 months ago.
We thought that the move to a different house and with new smells and all was going to make easy with both our cats but apparently it hasn’t changed, our other cat is a very sweet boy but it’s a senior now (he is 9.5 years old), and Pumbaa is roughly 5 years old, Pumbaa sometimes bullies our other cat which makes our other cat be upset at him, (not in a playful way), and this has clearly upset our other cat which has triggered him to chase down on Pumbaa, and Pumbaa gets super nervous and pees, because Pumbaa pees, our other cat get even more upset and has tried to attack Pumbaa a few times now and we’re afraid something else more serious could happen to Pumbaa.