Employment letter for self employee on 1099

[myvvisa]

Hi,

I am sponsoring for my in – laws, as I am a self employee on 1099. Could you please help me what documents should I send in place of employment letter?

Thank you

[immihelp]

Tax returns for the last three years.

If you had read https://www.immihelp.com/usa-visitor...sor-documents/, you would have got all your answers.