What happens to an 8 month old medial collateral ligament tear that I haven't had fixed, is there any need to at this point?
Depends. It depends on whether it has healed and your knee is stable.
No. If this was a minor injury like a grade 1 or 2 tear, with no or minimal disruption of the mcl; there are no associated injuries to the internal structures of the knee; and you have no mechanical symptoms of pain, swelling, instability, or locking, you can probably observe it without doing anything else. If the knee doesn't feel or act right, you should probably have it evaluated by a professional.