The headteachers of two Walkden schools have paid tribute to the three children who died following a house fire.
Demi Pearson, 14, was pronounced dead at the scene in Worsley, Greater Manchester, while her eight-year-old brother Brandon and seven-year-old sister Lacie later died in hospital.
The children's mother, Michelle Pearson, is in a serious condition in hospital while a fourth sibling, a three-year-old girl, is critically ill.
Demi was a pupil at Harrop Fold School in Salford, which featured in the Channel 4 documentary Educating Greater Manchester.
Drew Povey, head teacher, Harrop Fold school, said:
Emma Henderson, head teacher at Bridgewater Primary school said:
Greater Manchester Police said three men, aged 23, 20 and 18, and a 20-year-old woman have been arrested on suspicion of murder.
A 24-year-old man is also being questioned in custody on suspicion of assisting an offender.