My dear Mary. / Friday 28th is for thee - let / no one presume to ask me on that / day. / how good was Georgie - she never / reminded me that this was her birthday / when I said I was going to you. / - indeed I never know dates - / and live a bewildered life on / that subject. / Your affectionest / of BJs
Georgiana B-J was born on 21 July (not 28th)