[It's not uncommon for Billy to come to her with homework woes, and Lily marks her place in her reading with her index finger as she turns her attention to him, more amused than put upon. Billy was never much of an imposition.]

That seems to be a theme with you, lately. I can't say why-- it's not like you don't have the talent.

[By all accounts, Billy was a very gifted wizard, but they all had their weaknesses.]

Which part has been giving you trouble? I'll gladly help, if I can.