The child remembered as fearless may have been skilled at keeping fear private.

Children learn quickly which feelings a household finds easy. A child who worked out that fear was inconvenient, or that they were the one who coped, becomes very good at looking untroubled, and the family story then records bravery where there was mostly concealment. Adults remember the surface because the surface is what they were shown. Being seen as fearless can be lonely from inside.

If that word was used about you, you might revisit it gently rather than treating it as a standard to live up to. If a child near you seems unusually unbothered, leave room for the other version.