Tourist visa for spouse/child

[beegees]

We are applying for a B2 (visitor/tourist) visa for my wife and 9 year old child. I am employed in India and already have a 10 year B1/B2 since more than 3 years and have made multiple visits to US.

Wanted following inputs.

- my wife is not working since last 4 years and hence in the visa application, we have indicated myself as sponsor for both of them. all sponsor related references on site are for sponsor in US. is my being in india sponsoring them okay?
- the interview is scheduled for both of them togehter. do i need to accompany them for the child's interview or 2 of them alone is sufficient?
- we have an invitation letter from one friend in US. we are asking only for invitation not sponsorship. would this be okay?
- any specific documentation to be carried for the interview?
- we are saying they will travel with me on my next visit. do i need to get a leave certificate for myself?

any other guidance will be helpful. thanks

[immihelp]

1. OK.
2. You can't accopany them.
3. OK.
4. Read everything at http://www.immihelp.com/usa-visitors-visa/
5. No.

[beegees]

for point 2. somewhere i read both parents are required for minor children below 14. in this case do i need to give no objection certificate?