For your information they are properly called cotyledons (pronounced cot-till-lee-dons). Child, haven't you ever grown anything before? Except for grasses and pine trees, most common plants are dicots (it means the plant's seed has 2 cotyledons). Losing a "normal" leaf is not a good thing- the leaves are the food factories of the plant- but it won't do any great damage, either. The leaf will not grow back, but a branch will usually develop there. The branch, having been deprived of it's own personal food factory (the leaf), may grow a little slower than it's mate. Overfeeding and overwatering are to be avoided. More pot plants die from being "overloved", than die from lack of nutrients. Since your plants look healthy, just keep doing what you are doing. You may wish to top your plants to encourage more tops. If you remove the top growing tip of a plant, the side shoots all "decide" (it's a chemical process, actually) that THEY want to be the new top shoot- so you end up with more buds. :thumbsup: Good luck on your grow- Granny Storm Crow :stoned: