Visitor Visa for In-Law plus two children's one age 15 and another 10 - Document req

[Kathan Pandya]

Hi,

I am on H1b visa and i am sponsoring my Mother in Law, Sister in Law and there two children's (one age 15 and another 14). As they want to visit us in there school vacation time for 2 month.

I am aware about below listed documents that i have share with my in laws for interview purpose.
1) I-134
2) Bank Verification Letter
3) Bank Statement
4) W2 Form
5) Pay Stub
6) My and my wife passport + Marriage certificate
7) Birth Certificate.

Question -
1) do i need to fill separate I-134 document for Mother in Law, Sister in Law and two children's?
2) do i need to fill separate DS-160 form for children's as well or i can put there name under mother DS-160 form?
3) can i take interview together for everyone?

IN - Laws documents:-
1) all the financial documents they will be carrying with themselves.
2) Property documents
3) My brother in law won't be traveling or applying for visa due to work so do i need any document from my brother in laws related to children's as they are going for interview with mother?
4) My Brother and sister marriage certificate
5) do children's need any no objection certificate from School, as they are going to carry school ID card.
6) my brother in law business documents + there bank statements and an documents related to there business.

please let me know if i have missed anything above..