I know how worried sick our fur babies can get us & i'm a new Mama to Jaxson who is almost 12 weeks old. Me personally I have left Jaxson in his crate while my husband & I went grocery shopping but that was only after a week of him getting use to us & his crate & play pen! When we first got him one of us always stayed with him...it was mainly me though cause my husband is in the Army & works long hours so we just had to figure what worked for us! Jax is 3lbs right now & just got checked yesterday at the vet & he is very healthy! He eats great & is fully house trained! When we leave & come back he is sleeping in his crate & it doesn't seem to bother him one bit! We cover his crate with a dark blanket to make it feel like a wolfs den give it the dark feel & he has all his toys & things in there with him. We've left him no longer then 2 hours though & was on base the whole time. Good luck & you will find different opinions but everyone means well & know that everyone here was a new Mom at one point in time! Do what YOU feel is best & take into consideration the great advice given above! Happy 4th of July & God Bless!