the.com/second childhood

means The stage of old age when a person returns to childlike traits — simplicity, dependence, forgetfulness, or unguarded delight — as if the human life cycle loops back on itself.

from Traced to Shakespeare's 'All the world's a stage' speech in As You Like It (1600s), which maps a lifetime onto seven ages, the last described as 'second childishness and mere oblivion, / Sans teeth, sans eyes, sans taste, sans everything.' The phrase 'second childhood' grew out of that image — the idea that old age circles back to infancy's dependence and simplicity. Originally tinged with melancholy about decline, it's since softened in popular use toward something gentler: a late-life freedom to be unguarded and easily delighted again.