Thank you so much for the information about; 
1. Frieda Wachstock
  born 16 march 1934, in Borgerhout (Anvers), Belgium.
2, Esther Wachstock
 was born in the same place, either 10 january 1932 or Sept. 24, 1932.
Their brother, 3. Bernard-Willem ( Dov Zeev in Hebrew) Wachstock
   born 1st of June 1928 ? in Anvers also. 
There is one of their brothers who survived ( Yekutiel Zalman Salomon )He had 2 children and many grandchildren.
Here is what I know (we would love to have the picture you found)   Emile-Emmanuel Fitoussi is Yekutiel Zalman Salomon Wachstock's first cousin once removed's husband.
Yekutiel Zalman Salomon Wachstock
  → Frumet Wachstock
his mother → Jekutiel Zalman Rakower
her father → Itamar Ben Hur
his son (nee Rakower) → Ezra Ben-Hur
his son → <private> Fitoussi (Ben-Hur)
his daughter → Emile-Emmanuel Fitoussi
her husband

Emile-Emmanuel Fitoussi

Current Location:
NYC, New York, United States

Added by:
Started family tree January 11, 2013

Frumet Wachstock (Rakower) 

Gender:
Female
Birth:
1894
Kraków, Kraków County, Lesser Poland Voivodeship, Poland
Death:
1942 (48) (Perished in the Holocaust)
Immediate Family:
Daughter of Jekutiel Zalman Rakower and Golda Rakower
Wife of Joshua Wachstock
Mother of Yekutiel Zalman Salomon Wachstock; Dov Ze'ev Wachstock; Esthere Wachstock and Tamar Frieda Wachstock
Sister of Chaim Rakower
Half sister of Itamar Ben Hur; Hanna Grosman and Dov Zeev Alter Rakowe
Fruma Vakshtok nee Rakover was born in Krakow Poland to Yekutiel and Khava. She was a nurse and married to Yehoshua. . During the war she was in Belgium.
Fruma was murdered in the Shoah.
This information is based on a Page of Testimony  submitted by her brothers' grandson Avraham Cohen

Joshua Wachstock (Wachsstock) 

Gender:
Male
Birth:
June 09, 1897
Kraków, Kraków County, Lesser Poland Voivodeship, Poland
Death:
1942 (44) (Perished in the Holocaust)
Immediate Family:
Son of Lazar Wachsstock and Sara Rechel Wachsstock
Husband of Frumet Wachstock
Father of Yekutiel Zalman Salomon Wachstock; survived Dov Ze'ev Wachstock Perished in 1943 - Auschwitz,) Esthere Wachstock and Tamar Frieda Wachstock
Brother of Chana Wachsstock; Matilda Frumet Rakower; Chaja Wachsstock; Ryfka Freund; Temora Freida Freidman; Dovid Chaim Wachsstock and ???? ???? ???????

Yekutiel Zalman Salomon Wachstock

Gender:
Male
Current Location:
Antwerpen, Belgium
Birth:

Immediate Family:
Son of Joshua Wachstock and Frumet Wachstock
Husband of Lily Wachsstock
Father of Eddy (Ephraim Joshua) Wachsstoch and Francine Scharf
Brother of Dov Ze'ev Wachstock; Esthere Wachstock and Tamar Frieda Wachstock
Added by:
Sarah Daniele Mostovicz on September 29, 2007 Sarah Daniele Mostovicz is Yekutiel Zalman Salomon Wachstock's grandson's wife's aunt.

Managed by:
Eilat Gordin Levitan (Gordin) and 7 others

Eddy (Ephraim Joshua) Wachsstoch
Gender:
Male
Current Location:
Israel
Birth:
August 1959
Immediate Family:
Son of Yekutiel Zalman Salomon Wachstock and Lily Wachsstock
Husband of Miriam Haya Wachstock
Father of Eitan Wachsstoch; Ouri Wachsstoch; <private> Wachstock; Eyal Wachsstoch; <private> Wachstock; <private> Wachsstoch and <private> Wachsstoch « less
Brother of Francine Scharf
Added by:
Sarah Daniele Mostovicz on September 29, 2007

Francine Scharf (Wachstock)

Gender:
Female
Birth:
estimated between 1938 and 1976
Immediate Family:
Daughter of Yekutiel Zalman Salomon Wachstock and Lily Wachsstock
Wife of Benny (Benzion) Scharf
Mother of Phillipe (Dov Zev) Scharf and Caroline (Esther Matilda) Scharf
Sister of Eddy (Ephraim Joshua) Wachsstoch
Added by:
Sarah Daniele Mostovicz on September 29, 2007

Nira Lea Wasserman is Yekutiel Zalman Salomon Wachstock's first cousin.
They might be connected in other ways.
Show Me

Nira Lea Wasserman (Ben Hur)
 
Gender:
Female
Current Location:
Tel Aviv, Israel
Birth:
 1939
Jerusalem
Immediate Family:
Daughter of Itamar Ben Hur and Simcha Ben-Hur (Alfia)
Widow of Yaakov Wasserman

From: Laurence Klejman
Date: Mon, Oct 7, 2019 at 11:45 AM
Subject: WACHSSTOCK FAMILY
To: <eilat.gordinlevitan@gmail.com>

Hi ! My name is Ms Laurence KLEJMAN.
I looked at you interesting work on Wachsstock family on GENI.
I am a member of the association CONVOI 77, and we are trying to work with pupils on the biographies of the 1320 persons who were deported from France, Drancy camp to Auschwitz, the 31 July 1944, in the convoi 77. The latest large convoy before Liberation.

https://convoi77.org/#1529224568579-b7834465-d9a4

In this C 77, the two girls Esther et Frieda, who had escaped death in a UGIF Home for children, in Montreuil (near Paris) untill the nazi in charge of the camp, one of the most terrible, Alois Brunner, send the police to "clean up" the Children Home (for orphans, most of them)/
Frieda was born 16 march 1934, in Borgerhout (Anvers), Belgium.
Esther was born in the same place, either 10 january 1932 or Sept. 24, 1932.
Their brother, Bernard-Willem is supposed to be born 1st of June 1928, in Anvers also.

According to the Register of Anvers concerning belongings (store) to people deceased, and so on, in the Diamantary business, Szipa had a business, and his father Lazare, too.
  Szipa, or Szyja, is never mentionned as Joshua, and it's with the famliy name RAKOVER except on a Kazerndossin list but with a wrong birthate and place of birth. His wife is mentonned as Frymet Wachsstock, with a other birthdate as known. Are they the same couple, as it seems that these 2 families had cross marriages? Because the child with them is Paula Rakower, born 31 janvier 1933 in Anvers. (
archives Kazerndossin ; Afbeelding Transporlisten bekijken :    25/9/42  XII TRANSPORT)
https://www.google.com/search?q=Frymet+Wachsstock+d%C3%A9port%C3%A9e&safe=off&client=firefox-b-d&sxsrf=ACYBGNRO05W0zIbwXSWydfjdPds_-Dr44g:1570466843351&tbm=isch&source=iu&ictx=1&fir=J9DTAFQUM_GSNM%253A%252CtFOkr_CeSPipmM%252C_&vet=1&usg=AI4_-kRmGXeD-FqyeuuqyNmYQXCwEVi9JQ&sa=X&ved=2ahUKEwjghtHyzIrlAhUBCRoKHX66CaMQ9QEwAHoECAQQBg#imgrc=J9DTAFQUM_GSNM:&vet=1
A glance in the Civil archives of Anvers is necessary, I guess.

About Esther, there is a group photo (@Klarsfeld); you can see it on The Memorial de la Shoah website.

Can you tell me more about Emmanuel Fitoussi who has the Frymet portrait?
Best
Ms Laurence Klejman