To me it really depends whether you want to live in luxury or ordinary. If your kid is only 3 years old, then it's ok as you can start school latest by 5. Anyway if schooling is a problem, then I suggest you don't bring your family here. Familiarize with the living cost here before you bring them over.
Depending your area, you can get a 2 BR room furnished as low as 6500, transport ( if you get a driver ) = 700 per month. Food ( 150*30 = QR 4500 max ).