Rear chassis

I was working on my car yesterday and I noticed that the right rear of the car sits about 2" lower then the left rear. I got under the car and nothing seems to be broken could it just be old age and needs to be replaced? I haven't done anything to the rear of the car so it's all original suspension. Any thought?

Any thought?

replace the bushings, springs, and shocks.

does it have air shocks?

no air shocks on the car.