you should bring at least enough money to bridge 6 months. For toronto I'd estimate around $2000 per month (bottom) for a family, which would be a 1-BR apartment outside toronto (e.g. mississauga or scarborough) and does not include insurance, school/school items, clothes nor any luxury items such as a car, cable, savings, outside dining etc. and is limited to internet (6GB), pre-paid phone, etc. In addition, you should have enough money to be able to buy a return ticket just in case you won't be able to make it here.
If you do not have at least $10-12,000 you seriously should reconsider coming here until you've saved up that amount. Or you'd better come alone first and bring your family later once when your financial situation has been stabilized.