At the same time Steven and Amelia were destroying the Lost Diadem of Ravenclaw Horcrux, Heather was teaching the Yellow Quartet a Defense Against the Dark Arts lesson.
"Harry, Amy, Susan, Hannah, " said Heather seriously, "The spell I'm going to be teaching you today has a reputation as complex and difficult magic, but it really isn't. It is a protective spell known as the Patronus Charm."
"Aunt Amelia always told me that the Talking Patronus Charm IS complex and difficult magic but that the regular Patronus Charm was of average difficulty at worst, " piped up Susan.
"Mom always told me the same thing, " added Hannah.
"Then, does the existence of the Talking Patronus Charm that is complex and difficult cause confusion that leads people to believe that the regular Patronus Charm is complex and difficult when it really isn't?" inquired Amy.
"That plays a factor, " acknowledged Heather, "But the real problem is that Dumbledore and Snape have spent decades spreading the word about how hopelessly impossible the Patronus Charm is to discourage people from learning it."
"In other words, " realized Harry, "It was another ploy by Dumbledore and Snape to prevent innocent witches and wizards from protecting themselves against dark forces."
"That is true, " confirmed Heather, "But the protection that the Patronus Charm provides is not protection against Death Eaters or Dark Wizards, but vicious creatures, especially Dementors."
"What are Dementors?" chorused Harry and Amy as Susan and Hannah shuddered.
"Dementors, " said Heather slowly, making no effort to hide the uneasiness in her voice, "Are black hooded figures that resemble cloaks. They are blind and have no eyes. They move by gliding while giving off breath that emits a creepy rattling sound. Dementors fill the area around them with cold and hopelessness and they force people who get too near them to relive their worst memories."
Harry, Amy, Susan, and Hannah all gave involutory flinches.
"Can Dementors kill?" asked Harry.
"They do much worse than kill, " said Heather with a shiver, "When at their foulest state, Dementors pull back their hoods and suck their victims' souls out through their mouths. This is called the Dementor's Kiss. You can exist without your soul, you know, as long as your brain and heart are still working. But you'll have no sense of self anymore, no memory, no... anything. There's no chance at all of recovery. You'll just — exist. As an empty shell. And your soul is gone forever... lost."
"Where are Dementors most plentiful?" asked Amy curiously.
"The largest congregation of Dementors guards the wizard prison Azkaban, " answered Heather.
"That is very dangerous, " said Harry sharply, "Creatures like that can't be trusted. If Voldemort ever returns, he could easily persuade these Dementors to join him and even if he never does, there's bound to be some Dark Witch or Dark Wizard who could. Such creatures would have no loyalty and would not hesitate to turn for the right offer."
"You are right about this, " said Heather fretfully, "But Fudge has long insisted on keeping the Dementors even claiming that he only feels safe in his bed at night because he knows the Dementors are guarding Azkaban. Amelia knows about this and agrees, but even as head of the Department of Magical Law Enforcement, she does not have the power to overrule the Minister of Magic. That's actually one of the reasons I want you lot taught the Patronus Charm. I fear the possibility of having to deal with out of control Dementors."
"So, what is the Patronus Charm?" asked Harry in a businesslike voice.
"It acts as a guardian with the Dementor feeding on it instead of you. If it strong enough, it will drive the Dementors away. You know that a Patronus Charm is strong if there is a clearly defined shape and form and not just some vapor. This strong Patronus Charm is called a Corpreal Patronus."
"So how do you produce a Patronus Charm?" piped up Amy eagerly.
"You must focus on a powerful happy memory and speak the incantation "Expecto Patronum!"
Harry focused his mind on the night of the Welcoming Feast when the Yellow Quartet was officially formed.
Amy focused her mind clearly on the day Harry had gotten his follow up exam from Madam Pomfrey and how Harry had expressed such appreciation to her for the help she given him when he was dealing with the scar removal process and how much that acknowledgement had meant to her.
Susan and Hannah both concentrated as hard as they could on the memory of the day they had met each other when they were both just babies.
All four of them raised their wands and cried, "Expecto Patronum!"
Next nanosecond, a silver stag erupted from Harry's wand, a silver cat emitted itself from Amy's wand, a silver fwooper came out of Susan's wand, and a silver phoenix protruded from Hannah's wand.
"Well done all, " said Heather happily, "Dementors will not be long for here if they ever turn up while we are here.
"I was thinking of the day the Yellow Quartet was officially formed, " revealed Harry.
"I thought about how much appreciation Harry showed towards me for caring for him during the whole scar removal process. when Madam Pomfrey gave him his follow up exam, " said Amy emotionally.
"And let me guess, " beamed Heather, "Susan and Hannah, you two were both thinking of the day you met each other as babies."
"Yes!" confirmed Susan and Hannah proudly.
"All powerful memories and clearly competent witches and wizards CAN perform the regular Patronus Charm even at a young age, " said Heather clearly, "But, Harry, there's something you should know; James's Patronus was also a stag."
"Really?" asked Harry quietly.
"Really!" said Heather with a smile.
Harry felt tears of emotion starting to form in his eyes and running down his cheeks at the watershed moment.
Harry had discovered a piece of his father within himself.