Walking on eggshells usually means dealing with something delicate, fragile.
Actually, eggs are far from fragile. An egg has to be strong enough to withstand the weight of an adult bird during incubation and the tiny, weak baby bird within has to be able to peck its way out.
Is it true that if you touch a bird's eggs, the bird will abandon the nest? No, but don't do it! You don't want to alert those wily raiders, crows and jays, to that well-kept secret.
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