Who was killed by Jack the Ripper?

[FISHY1118]

A letter from Sickert's mother dated September 6th documents that Walter was in St. Valery-en-Caux at that time. "A letter sent by a French painter, Jacques-Emile Blanche, to his father described a visit with Sickert on September 16th." Casebook: Jack the Ripper - Patricia Cornwell and Walter Sickert: A Primer

See also Paul Begg's Jack the Ripper the Facts, pp. 410-411.

I ve had this discussion about said letter/s , its not conclusive in regards to Sickert s movement on the dates on the murders

The 16th you mentioned isn't a murder date and the 6th Sept has no year 1888 on it , if you can post it I'd like to see it . Cheers