I cannot help with the father's disappearance, etc.
Emihamn database:
First name: ULLA BRITTA K
Last name: BERGMAN
Age: 3 Gender: K
Parish: County: U (Västmanland)
Title/Note: DOTTER = daughter
Port: STOCKHOLM
Date: 1926 09 13
Destination: TIMMINS CAN
Fellows: JA
Source: ST 1926:689
First name: AINA REGINA
Last name: BERGMAN
Age: 25 Gender: K
Parish: County: U
Title/Note: FRU = wife
Port: STOCKHOLM
Date: 1926 09 13
Destination: TIMMINS CAN
Fellows: JA
Source: ST 1926:689
The Emibas CD has more details.
Post 909230
Bergman, Aina Regina
Hustru = wife (married woman)
b. 2/22/1901 in Nederkalix, Norrbottens län (Norrbotten)
Emigrated 9/2/1926
from Kallmora, Norberg, Västmanlands län (Västmanland)
to Canada
Source: Household Examination Roll, p. 1367
Emibas migration file ID: Norberg U 1926 021
Un-normalized versions:
Parish of birth: Nedre Kalix
Post 909231
Bergman, Ulla Britta Kristina
Dotter = daughter (unmarried woman)
b. 8/4/1923 in Jukkasjärvi, Norrbottens län (Lappland)
Emigrated 9/2/1926
from Kallmora, Norberg, Västmanlands län (Västmanland)
to Canada
Source: Household Examination Roll, p. 1367
Emibas migration file ID: Norberg U 1926 022
Ulla's father was named in her birth record.
http://www.arkivdigital.net (subscription)
Jukkasjärvi C:11 (1919-1924) Image 1940 (AID: v193163.b1940, NAD: SE/HLA/1010092)
Ulla Brita Kristina was born 4 August and was baptised 5 September 1923 in Jukkasjärvi parish in Norrbotten county, Sweden. Her father was the miner Karl Emil Bergman, born 2 November 1898. Her mother was Aina Regina. Her maiden name was listed but I'm not sure what it says. Aina Regina was born 22 February 1901.
The parents were married 15 October 1821.
Baptism witnesses were also listed.
The family was listed in the "församlingbok" on page 465.
Jukkasjärvi AIIa:18 (1915-1929) Image 2460 / page 465 (AID: v309844.b2460.s465, NAD: SE/HLA/1010092)
There was another child born before your Ulla Brita Kristina, but he died. I'm not sure about his first given name. He was ___? Emil born 1 March 1922 and he died 10 July 1922.
The father moved out to the USA 14 December 1923.
Judy