My sister (liberal) married a Dutchman and they lived in a small apartment in Amsterdam. Upstairs were immigrants who slaughtered an animal and the blood ran down through the floor into the apartment below.
My sister complained but remained a liberal. This was a couple of decades or so ago so many the scope of the problem wasn’t as visible yet.
Without knowing your sister, I typically hate the word liberal. Most are leftists, not liberal. Liberal implies greater tolerance, something most of them don’t have for anything other than what they are trying to ram down everyone’s throat.
All cultures are equal.