Here's the eldest boy's birth record:https://familysearch.org/pal:/MM9.3.1/TH-1951-23641-22677-66...
(Hungary civil registrations - Vas - Tobaj - image 90 of 443)
Item 31. Entered Mar. 21, born Mar. 15, 1913.
József, boy, Roman Catholic
parents: Tánczos Ida, occupation: household, residence: Horvátcsencs 33, Rom. Cath., age 19.
Tanczos Györgyné (Mrs. George Tanczos), informant
I've gone through the birth records in Tobaj starting around Mar. 1915, and haven't found any of the rest of the children, so it would seem that she (they) moved sometime before the birth of Franz.