The filming of Harry Potter and the Deathly Hallows meant lots of parts for younger versions of the existing cast and the epilogue providing glimpses of the next generation as Harry and Ginny, and Hermione and Ron see their children off to Hogwarts. Some pics of filming of the epilogue here.
Some of the lucky youngsters cast include:
10 year old Ryan Turner (represented by CS Management) from Huntingdon, as Hugo Weasley, the son of Hermione and Ron.
Ellie Darcey-Alden (represented by A&J Management) from Yarnton, as young Lily Evans (Harry's mother (Geraldine Somerville) in a flash-back scene)
Rohan Gotobed (represented by Abacus) from Poole, as young Sirius Black.