RON
He [Albus] hasn’t run away – he’s having a quiet moment – he’s got himself an older girlfriend [Delphi Diggory]—

HARRY
An older girlfriend?

RON
And a cracking one at that – gorgeous silver hair. Saw them on the roof together, near the owlery with Scorpius playing the gooseberry. Nice to see my love potion being used well, I thought.

Harry Potter and the Cursed Child - Chapter 3 :
See this quote in the Pensive -