I'm going to keep on keeping on with the pine shavings just because that's what we have on hand now. If I ever have issues with it I may eat my words, but all is well for now and that's all I've used. I may invest invest in some grit for them. Typically I don't give grit to youngsters because starter is soluble in water and turns into a mash in their digestive system without need for any grit. Thank you for your helpful response. I have used straw as bedding in a pinch when I was out of pine shavings but I'm not crazy about using it for babies. May look into sand though, that's interesting.