Venesa Baker imagines childhood as a time when a veil sits over our eyes, hiding the dangers and horrors of the real world. Because of it, children are happy, careless and naive. The speaker doesn't blame them for this; the veil is a kind of protection.
But the mood shifts as the poem goes on. Growing up brings seriousness, stress and depression, and the speaker says this now reaches kids "sooner and sooner." The repeated word makes the change feel like it's speeding up. The line about "happy memories / That could have been" is the saddest moment, because it focuses on what children never get to have.
The ending is quiet and bleak. The veil is "shredded," so it can't be put back. The speaker seems to feel regret and worry, and the poem leaves a wistful, sombre mood. Its short, plain lines make the loss sound simple and unavoidable.