"If you were really reliving their death, all you'd hear would be a screech of brakes and a horrific thud. Your parents died in a car accident. You know that."
-- Aunt Petunia Dursley (CC2.1)
Following the complete disappearance of his son Albus and Scorpius Malfoy from the Hogwarts Express, Harry Potter has a nightmare about living with the Dursleys and particularly his Aunt Petunia berating him. He also hears the voice of Voldemort again, a and sees Albus wearing the robes of Durmstrang Institute (CC2.1).
Harry Potter awakes and discusses from his dream with wife Ginny. As he talks about Voldemort’s voice and Albus dressed as a Durmstrang student, he realises what his son is going to try to do with the stolen Time-Turner (CC2.2).
Takes place in early September 2020, probably during the night/early hours the day after Albus and Scorpius escape from the Hogwarts Express and visit the St Oswald's Home
In this scene, Aunt Petunia is deliberately horrible and mean towards Harry, emphasising how disappointing he is. She shows no guilt about lying to him about the death of his parents either (CC2.1). The nastiness of her remarks verge on child abuse. It is quite horrifying and, in spite of the blood protection that it gives him (OP37), one wishes there was some other family Harry could have lived with - perhaps with Dumbledore or another member of the Order of the Phoenix.
From the Web
Pottermore: Harry Potter and the Cursed Child
The theatre production opened in the West End of London at the Palace Theatre on 31 July 2016, with Jamie Parker in the role of Harry Potter, Helena Limbery as Aunt Petunia, Sam Clemmett as Albus Potter and Poppy Miller as Ginny (Weasley) Potter: Harry Potter and the Cursed Child, Parts One and Two