1 The Discovery

It was hard to believe for James Potter that Professor Slughorn had never mentioned the adverse effects of a misbrewed potion at any point during the last six years of Potions class, especially considering that he knew the students, the Marauders and Slytherins in particular, would occasionally experiment with creating their own potions. It was only a couple of months after learning of what could have happened to them during their many potions mishaps that they were able to figure out precisely what damage they had caused themselves. It took this long solely because they were attempting to modify the diagnostic spell in such a way that the results would be written down rather than shown to the spell's caster, for it can not be performed on oneself and they were understandably reluctant to have someone else know what was wrong with them even before they did. They cast the newly modified spell on Remus first, knowing that his lycanthropy would likely have prevented any damage done by the potions yet would still appear on the parchment of all went as intended. When the charmed quill had written all it would they read over his results, finding that he had in fact sustained some damage, but that his 'furry little problem' had removed the effects before they set in. With this confirmation of the spell modification's success, they proceeded to cast it upon each other, with Sirius casting upon James, James upon Sirius, and Remus upon Peter. Peter had gone red and burnt the parchment that held his results after reading it, though the only one who noticed his actions was Remus as James and Sirius were both too busy being shocked and horrified by their own results. Several days later Sirius came to James and spoke of what he had discovered; that a mistake he made in brewing a potion during Third year had greatly lowered his inhibitions and made him reckless, a dangerous thing to be when there is a war going on and something that would likely bar him from ever becoming an auror or hit wizard as he had planned. James in turn told him of his own problem; that a potion he had attempted to make in Fifth year that he had inhaled the gasses of when it boiled dry during one of Sirius's detentions had permanently removed his ability to sire children. It turned out that he had not researched the ingredients thoroughly enough, as while he had known that one ingredient was often used in fertility potions and was thus deemed safe, when combined with another ingredient that he had used it would form a potion often fed to magical beasts to prevent breeding. Sirius, while shocked and appalled by both of their results, had managed to shove aside his own feelings to spend the following six hours convincing his brother in all but blood that he shouldn't break off his newly fledging relationship with Lily Evans. James persisted in his rejections of Sirius's arguments, right up until Sirius swore an oath to assist him in any way possible (without breaking any of the eventual marriage vows) in having children, at which point the Potter heir folded like wet cardboard and spent the next half hour sobbing in relief at the prospect of continuing his relationship with his girlfriend free of guilt.