The first sin Sherlock remembered committing was Gula, the sin of gluttony. He had been four and it was Mycroft's last birthday before he went away to school. Their Au Pair had made a large Croquembouche, complete with stars, spun sugar, sugar mice and with a nod to Mycroft's personal tastes, Meringue cat faces. The giant creation had been prepared the night before, and was sat in the formal Dining Room ready for the party the next day. Sherlock had difficulty sleeping, and had escaped his nursery looking for adventure.
He was stumbling along the corridor between Mummy's lounge and the library when he spotted the formal Dining room door was open. It was never open unless a party was imminent, and although Sherlock was vaguely aware it was Mycroft's birthday no one had mentioned a party to him. The last time they had had a Croquembouche in the house had been Mummies birthday party, and Sherlock had been allowed to eat all the sugared mice. So it was perfectly logical to his tiny mind he was allowed to eat Mycroft's as well, he climbed onto the table and started picking off the mice.
After what seemed to Sherlock was at least two hours, he had eaten all the mice, and most of the cats. He was suddenly aware that nobody was about, what if he was the only person left in the house, what if some terrible accident had happened and he was the only person alive in the house. Worse his little brain started to wonder what if he was the only person left alive on the planet. What if the world had come to the end and by some divine accident he had been left behind by mistake. In which case it was his duty to eat the rest of the Croquembouche, as it would definitely be a crime to let it go to waste.
Mycroft woke Sherlock up 6 hours later with a cry and a sob. Excited about his birthday, Mycroft had run downstairs looking for presents, and had instead found his baby brother, covered in sugar, choux pastry and chocolate unconscious in the center of the dining table. Worse his birthday cake, which he had been looking forward to sharing with his beloved brother, was almost completely consumed, and what was left was covered in the sticky saliva covered mess surrounding Sherlock.
Sherlock had been sent to his room for the rest of the day, and although Mycroft was very diplomatic about the event, he was very disappointed. Mummy was horrified and very angry with Sherlock, and Daddy had spanked him. Their Au Pair thought the whole thing was very funny, and created two smaller Croquembouche the next weekend just because she had loved both boys. Sherlock however was disappointed with himself, he should have been in more control, and he hated the nasty feeling he had in his chest and tummy for days afterwards. He made a decision there and then, never to be gluttonous again.