B2 Visa Holder Travel while Sponsor's Status is Changed or Moved out of Country

[pgauravaram]

Hi,

Have 2 situations Here:

1. My Mother have a B2 Visa, Sponsored by My Sister and currently My Sister is in India. Can my Mother Travel to USA and are the Options she has now.
2. My In-Laws have a B2 Visa, Sponsored by My Wife, when she was on L1B. But Currently My Wife is on H4 and she is in USA. Can they Travel and what are the options they have.

Greatly Appreciated in Advance.

[daggit]

1. My Mother have a B2 Visa..
2. My In-Laws have a B2 Visa..

What are the concerns if they have valid visas?