Finding Chamber of Secrets

[Donna]

No: HPFGUIDX 184141

Donna:
Okay, how did Tom Riddle find the entrance to the Chamber of Secrets?  We know it's in Moaning Myrtle's bathroom so, what was Tom doing in a girls' bathroom?  The trio was there to ask Myrtle how she died and she mentioned seeing the eyes by the sink which, as we know, is the entrance to the Chamber.  But, how did Tom know where the entrance was located?

[Non-text portions of this message have been removed]