Hi!
I am not related to the family Gustafsson, but my grandpa and my mother were born in Norra Strö, so I have done much research in that parish.
You are eight about Gustafs birth and deathdates and also about Annas and Carls birthdates.
The place where the family Nilsson lived on most of the time was called Övarp Nr 8.
Carl had seven sieblings all boys. one of them died as a smal boy. He was also called Carl born 01/29/1849, died 03/20/1853.
They other were:
Nils b 05/01/1837, he went to US with wife and daughter 09/22/1889
Sven b 05/03/1839, he stayed in Sweden, died there 1916. he took over the house after his parents, He married and had tenor eleven children.
One daughter Tilda took over the house after her father 1916. She lived there until her death 1962. She had five children.
Pehr b 06/30/1841, he moved 1859, but I have not found to wich parish
Jöns b 10/19/1845, he moved to Sörby 1872 and married, he got four children there. This family moved to US 03/21/1881 from Sörby.
Anders b 03/07/1846, he moved to US 05/28/1872. maybe he had been some years in Denmark?
Ola b 08/05/1851, he moved to US 04/13/1881
As you already know the father Gustaf died in April 1879, the mother Anna went to US 06/26/1885, she then used the surename Rundberg, which came from her fathers surename.
If you are interested I have a book about Norra Strö, there is a photo of the house where Carls brother Sven and his daughter Tilda had lived in.
Maybe it was the house where Gustaf and Anna also lived in long ago? I can scan the page for you but then I have to have your e-mail.
ellenhell