6/23/2021
Fay Bussgang found this among some records she had from Poland whose significance she hadn't understood until Barbara found Lajzer listed as the brother of her great-great grandmother in the Plock death record of Majer:

Ozorków Book of Residents (undated entry):
Lajzer Wolf Toronczyk, born April 16, 1849 in Żychlin Poland, residing in Ozorków

Lajzer Wolf was living in Ozorków in the same house, # 231, as Hersz Toronczyk, ancestor of Brian and younger brother of Fay's great-grandfather Chaim. His parents are listed as Majer Toronczyk and Małka Zylberberg, yes, the same Malka who was listed as Majer’s widow in his death record. As he is the oldest of the known sibs, Malka can be assumed to be the mother of all of them.

This means that Majer must be the son of Icek or Abram Toronczyk. Since Barbara and Ethan are linked through DNA to Fay and Brian and not to John (descendant of Icek), it is more likely that Majer was the son of Abram.

Polish Books of Residents and Other Lesser-Known Sources by Fay and Julian Bussgang

Success at Last!
originally published in Mass-pocha (Fall/Winter 1997) by Fay Bussgang
this is an excellent account of Fay's discovery of her Torunczyk roots

zoom in on these images

First column has House #, third column has males (his says Torunczyk Lajzer Wolf), 5th column has parents (Majer & Malka Zylberberg), next three columns give date of birth (16 April 1849), then comes column with town of birth (Town of Zychlin, Kutno Uyezd).