how many sets of leaves does it have? whats ur PH? fed any nutes? humidity can cause the plants to "perspire" and release large amounts of its own liquid,nutrients and any carbs/terpines (weed smells) or chlorophyll (green colour) it has. if ur others arent experiencing the same scenario tho, i wouldnt suggest humidity for first diagnosis. are they being grown 1 plant 1 pot, or has it enough space in the pot for root growth (a tap root hit the bottom of a 4" pot and stunted vertical growth,yet stil grew leaves and nodes, tho was very tightly spaced) what sort of soil are you using, does it seem compact and almost clay like? or is it like a mud that drys to a dust when left unwatered? or using potting mix or miracle grow?
its like ringing a doctor and asking diagnosis for a head ache without any other info. pictures would really help. can only speculate at this moment.
i thought ur problem BigBudz9704 was that ur seedling has yellow cotyledons due to having the seed husk on for a while, that is normal, usually when they are still in the shape of an upside down U and arent fully erected with open leaves yet, once they bend the right way, open up, and get some light, chlorophyll will fill the leaves in no time. same thing with seed husks keeping it from opening. note if ur stem is slightly green, thats chlorophyll so ur plant is "eating light" in some form and has the capacity for that.