1400 a month?
Which place?
Provide important info if you seek answer.

Thanks, well, it is monthly. Should there be any problem / financial issue by the embassy concerning my family?

Thanks Kiddo.  Sorry, forgot to mention it is in Hawaii, Manoa. I wait for your reply.

It depends which place you are going to. Is 1400 per month (I assume it is per month) before tax or after? If before tax, it is definitely not sufficient for a family of three in east coast or west coast states. I managed to support my family of three with $1800 per month before tax in upper midwest. However there is an option. If you apply for J1 visa, your spouse can work legally.

Hawaii is expensive bro

 THanks Sparty! I need to think about this. This is the PhD research assistantship. However, I have not confirmed yet the amount. I was assuming that it is not less than 1400 USD (after tax). Certainly it is after tuition waiver. Maybe it is less than that.

Hawaii State is very expensive.the sales tax is 13.5 percent which is comfortably expensive than most of the state

No. 1400/month will not be enough to support your family in Hawaii.

you need at least 2500/month to support your family even if you live poorly (not eating out, movies, mall, etc.)

 Hi Rajan, 

Here is my understanding of your situation: 
- You have an income of $1400/mth (without tax) and you dont have any other incomes
- Your University is at Honolulu 
- You have a child and a wife

So the straight forward answer to your question is NO. And this iswhy 

-- Hawaii is the most expensive state in the US. The cost of apartments (Studio) starts from $1100.
-- Raising a kid is expensive in US dude. Living cost of a child is higher than an adult. And you too have to support your wife. Think about that. 
-- I dont know about University of Hawaii or you program but the amout you got for your GA is very less. Also you dont know if your health insurance is covered or if you have to pay any other fee to your University. 
-- So if you are still in Nepal and you want to bring your wife and kid then I would suggest think deep about it and do a lot of research before making any sort of decision. 

What I would sugest is that since you already have the GA, join the university and please dont bring your wife and kid now. After a semester, find a University in cheaper US states and look for higher paying GAs and then once you are settled bring your wife and kid. There wont be any problem bring your wife and kid in F2 visa. Visa will be easily granted. 

All the best 

AE