I have twins too; 2 of the Blue moonshines growing in
my journal. That's why there are 6 instead of 5.
The seed looked like it was cracked, but it was 2 fused; didn't realize this until they sprouted.
I figured it was best to separate them in the first week, and it's turned out well. Both plants are going strong. The runt (named "miracle plant") has surpassed the one that was bigger at the split, and has extra purple stems. I'm glad I kept both.
I heard this happens in about 1/1000 seeds. Pretty rare