help regarding sponsorship

[immihelp]

We plan to go under self-sponsorship To USA to visit my sister-in-law.I Have the following clarifications:
1. Is invitation letter necessary ?
2.Can bank balance be shown in company account where my husband is sponsor?
3. Being a Govt servant will NOC suffice or should leave sanction letter also be submitted?
4. Can we take our children aged 10 &13 with us.

[immihelp]

1. No.
2. Yes, as long as the funds are available for you.
3. Either way is fine.
4. Yes, as long as they get visa too.