Without knowing more, if I had to guess, possibly looks like too much heat.
I do believe I’ve been staying between 78-85 temp wise, maybe the blue dream isn’t as heat tolerant as the others. I might try turning my portable unit down to 74, this unit is in the same room as the tent.
I could be entirely wrong. 
I also have the light on 20/4 right now. I did switch the exhaust to kick on at 80, before I had it on 85 to just help with really high temps. So I definitely think heat stress or maybe light stress? I gave them a healthy watering when I put my top dress and cover crop and have just been letting them do their thing ever since. There is still moisture in the deep soil but my top inch is drying out so I plan to give them some water tomorrow morning.
It could be water. Don’t forget to take into account that your cover crop is also using the water.
I’m not familiar with this soil to date but it looks to have stone in it. Is that just large perlite?
@Corndaddie pumice huh? I learn new things on this site wkly still. 
Me too, I believe they added it as a better form of aeration, but I’ll have to rewatch some of their videos to hear the reasoning again
Well I watered all my plants yesterday following the week 1 Build A Soil schedule. I have the house AC set on 74 and my portable AC set on 74 in the room my grow tent is in. So a pretty stable low temperature in the rest of the house and my exhaust fan in the tent kicks on when it hits 78 during the evening hours and 80 during the day. So it stays a little cooler during night time hours. I was actually hovering between 80-85 when I looked back at my temp tracker, so heat could have definitely effected the blue dream. I also realized my floor is slightly sloped so I think the light was a little closer to the back two plants than the front two. I raised the light all around and a little extra in the back. We’ll see what happens now that I’ve made these adjustments.
Need some help still trying to figure out what this blue dream is doing. Also slightly concerned with the newest growth on the others plants. Temps are sitting between 75-80 and RH is 45-60 with it being most humid in the morning. Any thoughts?
Competing Roots especially that crabgrass and clover - ever pull those roots up (outdoors in real Earth is one thing…Peat mix indoors bigger trick). Get it in a pot by itself, it will do better. But a transplant will make it worse before it can get better, From the looks of it If I had to take a guess…pH is way out of whack. Take a slurry sample on pH and PPM.
Temps go down RH goes Up
Temps go Up RH goes Down
Its Relative to Absolute Humidity & Temp. How much moisture the air can hold at a specific temp…warm air can hold more water. That’s why you have dew on your lawn in the morning and as the sun comes up it evaporates back into the air, because the warm hair can hold it in a gaseous form.
@Corndaddie things getting any better for your girls?
Sorry for the silence over the last two weeks. But here are some updates! Temperature has been staying 74-78 degrees, RH is 40-60 depending on when I watered and day/night cycles. It’s been pretty dry here in the Midwest but it’s starting to cool off. I’ve been watering my plants using build a soils schedule. I gave each plant besides my sad little blue dream some craft blend (general 3-5-4 fertilizer or something close to that) and worm castings. Also gave all of them a compost tea (nutrient tea) for veg about 14 days ago not long after my last post. I decided to just let the blue dream ride it out and see what happens. This was my second grow so I just said screw it, I have three healthy plants that should yield decent. Well after giving the compost tea to all of my plants they perked up including the blue dream.
Wanted to chime in although it appears you have the temp/humidity changed now. 85º consistently is too hot. The up cupping is the plant trying to defend herself from getting too hot. They curl up like that to cool off. 72 to 78 +/- is a good range to keep her in and it looks like that is close to where you are now so you should see some normal leaves/growth maintaining those targets.
Good luck growmie!!
Newest update from Monday
I too dressed all four plants as I saw pistols forming with everything they’ll need for flower. build a soil products used was craft blend again, buildaflower top dress, and kasha blend fermented grain. I then watered that in with another compost/nutrient tea this one focusing on flower nutrients. Used black strap molasses, buildaflower top dress, addition worm casting (some already in the buildaflower), Kashi blend, buildabloom (water soluble nutrients), and big 6 micro nutrients. Wow seeing my plants perk up the next couple days was awesome! Now we’re into flower and here’s how the plants are looking! Even the blue dream has some small buds developing!
Thanks for chiming in! Yeah @Newt was thinking temps too. That was where I started. I also read blue dream has a low nutrient tolerance so I am thinking the preloaded build a soil was too hot for it too start in plus hot temps! Looking much better now though thanks!!!
@Fieldofdreams whatcha think about that update?