Yes, its strange what they do and what they eat sometimes and we cannot predict everything. Id bet nearly every person here has a pan of oyster shell and granite in their coop, and this is an odd circumstances that has no one to blame. It does seem odd that it didnt stay in her crop, or that she ate more than would stay in her crop.
She could have been shoved away from other feed by a higher up hen, or been nervous about something and started gulping what she was near, or decided some other chick was NOT going to get this gravel, its MINE !!! err, hers chicken psychology is beyond most of us, dont drive yourself crazy over this.
We could dissect this for a year and a day and it wouldnt help much of anything. You noticed it, and are seeing that shes cared for. Its all anyone could have done.
She could have been shoved away from other feed by a higher up hen, or been nervous about something and started gulping what she was near, or decided some other chick was NOT going to get this gravel, its MINE !!! err, hers chicken psychology is beyond most of us, dont drive yourself crazy over this.
We could dissect this for a year and a day and it wouldnt help much of anything. You noticed it, and are seeing that shes cared for. Its all anyone could have done.