lol, I knew you were going to ask me that, so just to elaborate, and based on my albeit often stoned understanding, there are a few ways this might happen, there might be multiple ovules in the seed, so you might get identical twins, or fraternal twins or you might get apomixis, where there are two sprouts but one will be homozygous haploid, while the other will be heterozygous diploid. This happens because embryogenesis in one of the double-seedlings arises from the zygote after fertilization and the other is derived from an unfertilized gamete, so no male pollen is involved. The one derived from the unfertilized gamete will only contain the mother’s dna, it’s a half copy, so they are always weak and malformed but such a freak is highly sought in plant breeding, and various food crops use sterile lines and embryo rescue etc. and gene doubling to create double haploids as they massively speed up the whole breeding cycle. You get a true breeding variety in one step.
Normally haploids are gene doubled to double haploids using chemicals like colchicine.
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