estate has Canadian accounts cashed in by Canadian son

[schirallicpa]

Taxpayer passed away during 2018.  She was an American citizen but had relation in Canada.  A few years back she inherited money that was put into an Ameriprise account.  Her son, who is Canadian, was beneficiary on the account.  He has since transferred the funds in Ameriprise to his own account.  

Other than the usual reporting of div and capital gains on the account on the 1041, is there special reporting for the transfer of the funds to Canada?  The son says he has already paid the Canadian tax on the transfer(?).  Also, since the son will be getting an K-1, he will have to file and pay tax in the US.