I like mutants and never kill them. Normally they get that part done on their own. But some grew out of it to become beautiful plants.
Looking forward to see how your little mutant does, hope she'll be strange but healthy!
Btw. if you have seed hulls sticking to the seedling don't try to pry them open or take them off!
A drop of water often works, softening the shell. Or a small piece of wet toilet paper for a couple hours when that's not enough.
I only had that problem when the rH was quite low, keep an eye on that when planting seed.
My mutant Malawi is developing in 3's. After stalling and being very sow (and now it is shaded), it now has 3 main shoots. The leaves have 3 lobes but they are still young. I might replant it for giggles and see what comes from it.