Since his arrest on Tuesday there has been mounting evidence to suggest that the girl’s father may have killed her.
Prosecutor Wilhelm Storck wants to have the man detained on suspicion of murder.
Court proceedings for the issue of a detention order have been set for 2 p.m. on Friday.
A 60-year-old woman held on suspicion of harbouring a known criminal was released on Thursday evening. The prosecutor judged that it was no longer necessary to detain her, though the suspicions against her still stand.
The girl was found dead in a small house outside the southern Swedish town of Motala on Saturday.
The two suspects called an ambulance to the scene but a postmortem later showed that she had not died of natural causes.