I wonder what they did?

Well, that Henry is Alfred's brother, which means they both left home prior to 1871 census. I wonder what they did?

He's rather like a demanding toddler.

Now that's interesting. Although, as with all family research, I could follow a wrong trail. I need to delve ... Anyway, my suspect's brother, Henry, born in Islington, was living, according to the census of 1871, in the borough of St Leonard Shoreditch, London, and which, according to Google Maps, is a mere ten minute walk from Brick Lane. Henry worked as a baker, a similar occupation to Alfred (Jack) before he ran off to join the army.
I'm supposed to be writing about Mary and then 'Jack' demands attention. He's rather like a demanding toddler.

Secret files on Jack the Ripper

SECRET files which name four new Jack the Ripper suspects will not be released to the public.
Retired murder detective Trevor Marriott has fought to have a 900-page dossier on the 1888 Whitechapel ­murders released.
But a tribunal last week ruled they must be kept ­hidden. Scotland Yard said living ­relatives of the ­suspects could be ­attacked.
It added that releasing the papers which name “grasses” would jeopardise the ­recruitment of ­modern-day informants.

Protecting themselves from embarrassment more like! 'Jeopardising grasses' after 120 years? Utter nonsense

Daily Mirror

Mary Kelly as feisty but likeable

Right. How to create Mary Kelly as feisty, but likeable, with a streak of independence, and without our 21st century perspective of liberated womanhood?

I’ve decided to write a Hitchcockian style story, whereby we know the killer’s (Jack the Ripper) identity but Mary Kelly is ignorant.

A new departure. I have the story in place, which is unlike me. 

I'll begin the story circa 1876.

Maybe.

 Alfred Long's census record, 1871, showing he's two years older than his actual years. He was born in 1855.

Alfred Long's census record, 1861, showing his/family London, Islington, connection.

Maybe the census was written incorrectly.
Maybe he had no ill motive to use an alias, with that rather mockingly toned, James Short, when he joined the 9th Lancers in Aldershot.
Maybe that bullet wound in his forehead didn't cause traumatic brain injury from battle in Afghanistan.
Maybe he didn't suffer from post traumatic disorder.
Maybe he didn't have a pesh-kabz knife that could piece armour, stab and slice. 
Maybe 9th Lancer's nickname, the Delhi Spearmen, meant nothing to him.
Maybe the history of his unit was meaningless. (officer's wives had their unborn children ripped from their bodies).
Maybe he thought that piece of cloth was important because he had telepathic powers.
Maybe he didn't have to see in the dark. Not when he carried a lamp.
Maybe he had a silent step because he wore police issued india rubber boots.
Maybe he could approach women with impunity because he was a policeman.
Maybe the writing is on the wall, and Alfred long is Jack the Ripper.

Another coincidence surrounds Mary Kelly

Just when I think that's it. No more coincidences, what happens? This happens.
Okay, he's Dutch but I doubt his name is Maria. It is Maryn, Martyn, or Maartyn, one time lover of Mary Kelly and Adrienus L Morgestern's brother. But look at the names in the family unit, Maria and a Jeannette.
Census 1881:

Maria A Morgestern
England and Wales Census, 1881
Name     Maria A Morgestern
Event Type     Census
Event Date     1881
Event Place     Fulham, London,Middlesex, England
Registration District     Fulham
Residence Note     Victoria Rd
Gender     Male
Age     26
Marital Status (Original)     Single
Occupation     Gas Stoker
Relationship to Head of Household     Brother
Birth Year (Estimated)     1855
Birthplace     Alphen Priel (F), The Netherlands
Page Number     46
Registration Number     RG11
Piece/Folio     74/23
Affiliate Record Type     Household
Household
   
Role
   
Gender
   
Age
   
Birthplace
Adrienus L Morgestern        Head     M     33     Alphen Priel (F), The Netherlands
Jeanette S Morgestern          Wife     F     28     Mzerbo (F), The Netherlands
Johanna C Morgestern         Daughter     F     7     Proogendael
Maria Morgestern                Daughter     F     6     Proogendael
Wilhelmin L Morgestern     Daughter     F     4     Fulham, Middlesex, England
Petronella C Morgestern     Daughter     F     3 M     Fulham, Middlesex, England
Maria A Morgestern           Brother     M     26     Alphen Priel (F), The Netherlands

Oh well.

Good, good. Mary Kelly at last has a voice. The storyline is in place....just need to write the book. I've written 30,000 words, most of which, I shall discard.

Jack the Ripper had a frontal lobe injury.

 My suspect had a frontal lobe injury. He was shot in the forehead. What's interesting here is the mention of witzelsucht; Jack the Ripper's letters took a mocking tone.

This lobe is often cited as the part of the brain responsible for the ability to decide between good and bad choices, as well as recognize the consequences of different actions. Following a frontal lobe injury, an individual’s abilities to make good choices and recognize consequences are often impaired.
Euphoria and disinhibition are described. The euphoria is not that of a manic condition, having an empty quality to it. The disinhibition can lead to marked abnormalities of behavior, sometimes associated with outbursts of irritability and aggression. So-called witzelsucht has been described, in which patients show an inappropriate facetiousness and a tendency to pun.

 Witzelsucht (from the German witzeln, meaning to joke or wisecrack, and sucht, meaning addiction or yearning) is a set of rare neurological symptoms characterized by a tendency to make puns, or tell inappropriate jokes or pointless stories in socially inappropriate situations. A less common symptom is hypersexuality, the tendency to make sexual comments at inappropriate times or situations. Patients do not understand that their behavior is abnormal, therefore are nonresponsive to others' reactions. This disorder is most commonly seen in patients with frontal lobe damage, particularly right frontal lobe tumors or trauma.

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