Death in NY, Resident of RI

[mdtra]

My father-in-law passed away in NY, but was a resident of RI. We have no will, but I understand he has his daughters as beneficiary of his retirement account, and co-account holders in some stock funds and bank accounts. I assume the death cert. is issue in NY, but what is the next step?? Can the girls just take over the stock and bank accounts after switching the TAxpayer ID to themselves, or is this all handled by probate?