Does anyone have experience with Pectus Excavatum ?

So, when my son was born he was diagnosed with Pectus Excavatum. Meaning, his sternum and ribs grow inward instead of outward, causing a bowl in the center of his chest. The drs all told me he would probably outgrow it and it was no big deal. So I let it go. Fast forward, he’s 3 1/2 now and the bowl just keeps getting deeper. You could literally stack quarters in it at this point. So I took him back to the dr and demanded he see a specialist. He goes 6/4/21 and I’m scared to death. I’ve done some research and it can cause his heart to be pushed into the left pleural cavity and put strain on his lungs. Recently, I’ve noticed he gets out of breath quickly when running. There are surgeries he could undergo but he’s a baby! I’m freaking out now because he might need to get an MRI, I can’t even imagine if he has to get surgery. I’m just looking for advice or personal experience and how things turned out for you.