F2A 864 form question

[rzjz11 0]

Question for my friend:

 

My mom has a greencard, she is applying green card for her husband(my step father). She just came to the US 2 years ago, she doesn't have income and she lives with me and my husband.

 

For I-864 form, Part 1, should I put in her name or my name if my husband and I both are join sponsor for her husband? We both have jobs.

 

Please see the attachment highlight sections, which one should I choose and whose name should I put in?

 

Thanks.

 

If I put my mom's name in part 1, does it mean my husband and I both need to fill out I-864A forms seperately? So in total 3 forms.  I-864 - my mom, I-864A my husband, I-864A I fill out the form too.

 

Thanks.