I have a litter of 6 pups and they're doing great. Eating, sleeping, growing. However, yesterday I noticed some loose yellow poop in their box (mom was outside and didn't get to it) and again today. Is this something I should be concerned about? Does it have to do with the mother's diet? She's on a mix of puppy food and canned wet food, with some raw meat in small quantities as well. Any advice would be appreciated.