I've got 2 seedlings that retained a (membrane?) after the seed shell came off, and they're not opening after 24+ hrs after popping. These 2 grew twice as high after popping, but didn't open. I took some tweezers last night and gingerly as I could peeled the membrane off, but they haven't opened up 16hrs later. The one in the back left looks a bit different as I nicked a small piece of the round leaf off when removing the membrane. I started 3 of this strain, and 2 of those 3 did this. What happened here, and is there anything more I can do to help them open?