Rotavirus vaccine is drops in the mouth like the older polio vaccine.
Yes  it is new,  Must be given before 6 mo of age. If
your sister is BF and stays at home there is little chance her baby would
get the disease, but if she goes to the grocery store, church or family
gatherings then her baby is exposed and this is one more disease that can
be avoided (having had vomiting kids in office all month and several young
babies admitted for vomiting and dehydration.  It is NOT pretty in Atlantic
City this month!)  Sincerely, Pat in SNJ