Who should file Visitor Visa extension

[vvsrb]

Hi All,

Here is the situation we had.

My mother in law got Visitor Visa sponsored by her Younger daughter's family few years back(2009) and then she arrived in USA and satyed for 5 and half months and went back to India.
This year she came on visit again to USA for second time. This time she came along with her Elder daugther's family and now she wants to extend her visa for few more months after the allowed period of stay(Nov14). But, her port of entry for first visit is SF and this time her port of entry is Chicago.

Question is, who should apply for her Visa extension on her behalf, her younger daughther's family(original sponser of B2) or elder daughter's family(her current port of entry). Does the port of entry make any difference when applying for Visitor Visa Extension.

Please help us with requsted information as she have her I-94 validaty till Nov 14th this year.

Thanks in Advance.

[kabkaba]

Your mother files her own application. Other people may help her write it.