I have some hairs like that. The majority of my hair isn't like that at all, but there are enough for me to notice. The hairs I have like that are also wavy, but not with a defined wave pattern, so they stand out more when they are short, baby hairs. I think they are from coarser hair strands than my overall coarseness, or from wavier strands than my overall texture; maybe both. I know that mine are natural and not from any heat damage or mechanical damage, but I suppose a similar effect could occur from heat or mechanical damage.
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