Ciao.  When our mama passed away,

Ciao.  When our mama passed away, she left her estate to me and my three siblings equally.  She lived in the UK , as do I and my siblings.  She owned a flat in Italy and had added my brother's name to the ownership as he visited Italy more than the rest of us.  My brother would like to add us to the ownership of the flat, as that is what our mama wanted.  Can this be done in the UK or must it be done by a Notary in Italy?  I am in poor health and the journey would be difficult, and the flat is up three flights of stairs.  We also wonder what would happen to the flat if my brother passed away?  This is why I wondered if this could be done in the UK?  I would greatefully appreciate any advice.  Thank you.