"You'll find your son again, Harry Potter. But then you could lose him forever."
-- Bane the centaur (CC2.5)
Harry Potter encounters the centaur Bane in the Forbidden Forest. Bane reminds him that the forest land has belonged to the centaurs since the Battle of Hogwarts and that Harry is trespassing without permission. However, although unwilling or unable to help find Albus in the forest, he warns Harry about the black cloud “in the stars” around his son (CC2.5).
Takes place early September 2020, probably during the second day after Albus and Scorpius escape from the Hogwarts Express and visit the St Oswald's Home - at the same time or shortly after the previous event
In spite of possible misrepresentations and overall vagueness of any readings of the stars made by the centaurs or anyone else practicing Divination, Harry takes what Bane says too seriously (CC2.5). This will cause his relationship with his son Albus to further deteriorate.
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 and Nuno Silva as Bane: Harry Potter and the Cursed Child, Parts One and Two