It is the family themselves who decided to test the sock for DNA, after the police did not want to do it.
Now DNA has been found in the sock, which can be linked to the missing 17-year-old - which Swedish radio was the first to tell.
It is the family itself that stated that the DNA test shows that the sock belonged to the boy.
Searched every weekend
Gustav Bäck from Ljungby has been looking for the 17-year-old almost every weekend since December, and was one of several who found the sock.
It was first noticed two weeks after the disappearance, but was left behind.
After another ten days, Gustav Bäck found it.
- We called the police and they came.
But they let it lie.
Then the mother had to come and pick it up herself, he says.
At the site, Gustav Bäck has also found arrows and figures drawn in the ground - something that has attracted the attention of those who are looking.
But there is no evidence that they have anything to do with the disappearance.
See the pictures from the site and hear Gustav Bäck tell about the find - and how it affects the search for the volunteers.
No difference for the police
The police did not want to do a DNA test themselves, because they did not suspect crimes behind the disappearance.
Now that a result has come, the police say that it is irrelevant to their search work.
- This makes no difference then to now.
It does not change our view of how we have worked both before and after the discovery in this area.
We consider the area to be well-searched and still have no suspicions of crime.
The police are not currently looking for the 17-year-old.
- There is nothing that we organize but Missing people conducts searches in contact with us and that is something we welcome.
We will search the watercourses in Lagan again when it gets a little warmer, says Robert Loeffel.
But volunteers continue to look for the boy - this weekend in the area where the sock was found.