Yitchokm: sorry I tried retracing the info I remembered and I was partially wrong.
All she mentioned was about her uncle Rav Johnathon Rothschild’s from Washington Heights levaye in a Pre-Purim Shiur this year. After that I researched a bit, and some interviews /bios online mention her father being from Switzerland and a “scion of the famous Rothschild Family” without mentioning the words banking. That’s how the seeds were planted in my head…
So I couldn’t vouch for it, although it was worded to imply that she was from THE ROTHSCHILD FAMILY.
Bear in mind that there are thousands of Meir Anschel descendants, and not all are in the online wiki pages etc.