Seedling not looking good

look in my last diarie the cripple was the best at the end

The yellowing actually looks like early stages of nitrogen deficiency. Have you fed them any nutrients?

Just dont over water her thinking it will help, it will kill her off. As long as she doesnt get rot and doesnt fully dry out she will recover fine. She will end up being the smallest thou- every day shes recovering the others are growing bigger, so keep that in mind. Id let her go thou, never judge a bud plant by how they look in veg.

Quite simply, not all seeds make it, they are not all guaranteed to grow into perfect plants. It might pull through, so no need to give up just yet. It probably has nothing to do with anything you have done, it is just a less than perfect seedling.

Give her a little more time. Since the other 3 look good, it may be a whim of nature that she is a bit behind. If the growing factors weren't right, you would see changes in all four.