cough and collapsing

by Ali

I have a 13 yr old pom and cocker spaniel mix, i've heard that poms have a tendency to develop a collapsed trachea. my question is that he coughs a lot and just starting last week if he coughs alot sometimes he'll collapse... during the coughing fitit'll look like his legs will go rigor mortis and stiffen and he falls, he cries during the collapse but gets up like nothing happened.

i know ineed to come to grip with the fact that he's getting old and we might not be able to do anything for him and may have to put him down, i was just wondering if this has happened to anyone elses dog.