Thanks.This email tells there is something additional which your parents need to do for medical exams. They will get to know from the doctor. Sometimes applicants need additional screening if there is any abnormality in the medical report.
Actually our panel physician already asked my dad to do additional test before sending the report to CIC because they have seen so many similar cases, and the test was done on Nov 15.
The panel physician said it usually takes 6-8 weeks before CIC sent the additional request. We can either wait for the request or do it in advance as the result will take 8 weeks to show. I didn't expect it to arrive so soon.
CIC is really fast right now.