A joint sponsor is required when the primary sponsor's income or assets are not sufficient to meet the threshold of 125% of the Poverty Guidelines.

Visa overstay and a different citizenship

It does not matter that you now have a new citizenship. You cannot escape the consequences of removal/deportation by changing your citizenship.

Generally speaking, a valid advance parole allows you to return to the US, however, it is always best to consult with an immigration attorney prior...

What is the likely outcome of this situation?

A lot depends on what his status is in the United States. Domestic battery charges are very serious, and, if convicted, he could be subject to...

Shall I fill the mailing address of the applicant overseas? or can I fill it with an address in USA

The I-864 form comes with detailed instructions. You can find the form and the instructions on www.uscis.gov. If you have read the instructions and...