If I join a program in August 2017, after what time period, can I call my wife and children to US, so that I can support them financially and fulfill their needs ?
Usually, if you show enough funds availability, you can take your spouse and child anytime to US. That’s the key requirement for inviting them. If you have funding, etc, you can use that as well. You can speak to your DSO ( student advisor) at the school to get more info and details.