Khan’s school, Bourne End Academy, also issued a touching tribute on the day pupils returned after the half-term break.
“As a student, Sunnah grew in confidence over her first ten months at Bourne End. She developed a bold and happy personality which resonated throughout the school community,” a spokesman said.
“Her energetic character and fierce sense of loyalty meant that she had built strong and positive relationships with her peers and teachers. She will be enormously missed.”
A family friend told The Telegraph that Khan’s funeral had taken place at High Wycombe Central Mosque on Saturday afternoon.
He said her family and the local community were still “not any wiser” about what exactly led to the deaths of the children.
The Dorset Belle boat was impounded by police after the incident and a man in his 40s, described as being “on the water” at the time of the deaths, was arrested on suspicion of manslaughter.
Dorset Police confirmed that the man, who was released on Thursday under investigation, was not known to the victims.