Hi Devesh,
If you are coming here on work visa, please ensure you iron out your child's medical insurance with your company. Canada has universal health care system for its citizens and immigrants (which mean thalassemia treatment is free). However, if you are coming on work visa as foreign national, you are not considered as immigrant or citizen, you have to buy medical insurance (which can be expensive).
Not trying to discourage you, but since your child has a pre-medical condition, I am not sure if insurance companies are willing to offer you policy (nature of humans). I would only imagine, a monthly transfusion with doctor appointment and exjade etc. can cost you more than $1,000 per month.
Please talk to your company about your child and possibility of medical insurance.