One of my favorite Swedish database at Ancestry.com is Indexed Birth records, 1860-1941. This is some of the information from Ancestry about the database:
Records in this database were created by Statistics Sweden (SCB), a government agency established in 1858 that extracted and transcribed birth, marriage, and death information from parish record books from 1860 to 1941, including these birth records.
So, it is extracted and transcribed information and should be compared to the primary source. Since it is indexed and searchable it is nice and most of the time easy to find the information you are looking for.
For example, if I would like to search for children with a father named Jöns Berlin and mother named Else Månsdotter I would fill it out like this:
Fathers name: Jöns Berlin
Mothers name: Els?
Why, well, first of all, typing in Månsdotter might get the correct matches but sometimes it might be that Månsdotter would be replaced with Månsson depending on what area and frame of time. If I would get a lot of matches I would try to refine the search of the mothers name to Els? Måns* that would cover both Månsdotter and Månsson.
Her first name being Else could easy be mixed up with Elsa (and in this case it has been once) in any part of the process, being when the transciption was made back in the days or being indexed at Ancestry.
This search is great if you are looking for siblings in a family.
The result: Top four matches are Jöns Berlin and Else Månsdotter and their four children, Emma, Nils Anton, Anna and Emil Anton.
Good luck! The man in the picture is Nils Anton, the second child of Jöns Berlin and Else Månsdotter, my great grandfather.