Car stops while running, but put in reverse it runs

Hi,

This sounds like either it is low on fluid or the pump and valve body inside the transmission are failing. I am a little confused about the small ball on the tire though. Is this a bulge in the tire or was there actually a ball there that she took off? If so, can you send a picture of it? This doesn't sound related to the transmission issue no matter what it is but I am just curious. Thanks