Louisiana-Brook died after the blaze broke out in a static unit at Sealand’s caravan park in Ingoldmells, near Skegness, on Monday night.
Her three siblings, aged under 11, and their mum Natasha Broadley, from the Newark area, managed to escape.
Lincolnshire Police is currently treating the girl’s death as unexplained.
Tributes have been paid to Louisiana-Brook on a gofundme page set up by a friend, with more than £12,000 raised for the family.
The force said the investigation into the cause of the blaze was expected to take “some time”.
The family had been on holiday at the caravan park when the fire happened at about 22:30 BST on Monday.
The blaze resulted in about 50 people from nearby caravans being moved to emergency accommodation set up by site owner Laver Leisure.
Officers are appealing for witnesses or people with footage of the fire to contact them.
Sealands is a coastal holiday home site with 263 static home plots, many of which can be rented.
It is popular with holidaymakers and is close to Fantasy Island theme park and a Butlin’s holiday camp.