Who installed the swing? If it was a big company, did they give you a warranty? Was there an expectation that your family would maintain the swing and its safety?
If it was just some handyman working in your backyard to put the swing up, I wouldn't bother to try to get compensation, it would be pretty futile. If it was Toys R Us, possibly you could.
When looking up what kind of warranty you were given, also look for any recalls of that model of swing. (That is, if it was a commercial product and not just made by someone who was handy with wood.)
Please keep in mind that unless this is a fight that has already been fought (such as a big lawsuit against a big manufacturer or retailer and they have already admitted fault), there is no "seeing a lawyer to get compensation," like going there and getting a payout. You would need to sure the manufacturer or the installer, and that is if you have a good case. If it has been 4 years, however, I would let the lawyer you see be your guide .... unless this is a known hazardous swingset or was set up by someone who has already had to pay out awards because they made errors, the manufacturer or builder would claim that by now, the care and maintenance of the swing so it stays safe is up to the owner, not the problem of the builder any more.
You get compensation for degree of injury and loss of income. If your son isn't injured (it's a little hard to tell the degree of his injury - you say it isn't "traumatic") and if you only had to miss a few days of work, it's unlikely a lawyer will take that on. Not worth the time.
I agree with Annie's posts.
And there are so many more legal questions - after 4 years, should you have been responsible for maintaining the swing and noticing it may be deteriorating? Was the collapse of the swing of the nature that it's a true miracle your son wasn't killed, or was this more a bump on the head type failure of the swing?
IMHO, when in doubt, don't sue. If it just ruins your year.
