Behind the hidden door was a flight of crumbling stairs leading outdoors, ending in a tiny clearing surrounded by high rock walls. Edgar never told Lolotte about this discovery, and would sometimes go there when he wished to be alone with his thoughts. The tiny seedling he discovered growing there one day was just as mysterious, but Edgar was determined to help it grow. The sight of the bright green plant slowly unfurling brought peace to his soul, and helped distract his mind from Lolotte -- the evil woman who claimed to be his mother.
All of that seemed so long ago with the appearance of the peasant girl with the bright blue eyes and golden hair, whose name Edgar had only recently learned was Rosella. He may have persuaded Lolotte to free Rosella from her imprisonment, but when Lolotte declared that he and the girl were to be married the following day, he was so shocked that he found himself completely incapable of speech. Even when Lolotte stated that Rosella was to sleep in Edgar's room and Rosella was led there, Edgar was unable to even ask his mother where he was meant to sleep. In fact, she barely seemed to acknowledge him at all as she left the throne room and continued up the stairs to her room, gleefully musing out loud about how much power she had now that she possessed Pandora's Box, which she had forced Rosella to retrieve for her.
Edgar retreated to his usual spot, angry at his so-called mother but even more angry at himself for not speaking up to her. His anger quickly turned to despair as he thought about Rosella. Despite his feelings for her, he couldn't cast aside the cruel reality of what he was. Someone like her could never be happy with someone who looked like him, especially if she were to spend her days inside this gloomy castle with Lolotte as her mother-in-law.
As he lay on the ground, he found himself staring at the seedling he had nurtured, which by this time had grown into a small rosebush with a single red rose blossoming upon it. The sight of the beautiful flower trapped within the barren clearing made Edgar realize that he had to do something. For Rosella's sake, he couldn't let Lolotte's plan succeed...and as he continued to study the rose, a plan began to form in his mind.
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I've sometimes wondered where Edgar disappears to in King's Quest IV after Rosella gets locked in his room, as well as where exactly he got that rose he gives her which helps her escape. Here's a scenario that answers both questions.