Okay. I have a 4 yr old, a 2 yr old and a 10 month old. The two older girls both went through a dog food eating stage and they are as healthy as can be. My 2 year has even gotten to the cat food (climbing for it), sitting down with the bowl and eating it like it is snack! We definitely discourage the kids from doing this, but kids are kids, and they are curious, and when hungry and not totally verbal, will eat whatever they can find!
My youngest is just starting to get curious, and yes, I expect she will too go through a dog food eating stage. She has not tried to eat anything yet, but we do not leave the food down all day. We feed our dog at dinner time, so we do not have the same issue. The cat food, which is out all day, fortunately is off the floor on the cat's own counter.
Dog water WILL get everywhere. BUT it is only water. Just make sure you have some old towels around for easy clean up and extra dry clothes for your little one. You will find yourself getting clean dog water frequently as well, as kids love to put things into bowls of water...
All said, I have never had any of my kids (knock on wood) choke on either the cat food or dog food. You have to be vigilant, but I do not think you need to worry if a few kibbles get ingested...I would be more worried about your dog getting anxious over your little one invading her food. My dogs have always been very docile when it comes to food. But if your dog is already a worrier when it comes to eating, you may need to work with her starting NOW and slowly moving her food to a more kid friendly place that she can get to but your baby can't. Is there a room where you can close the door and install a doggie door on for your dog? Until your daughter learns to crawl through that, which will come later when she is less likely to choke, your dog will be able to get to her food in peace and you won't have to worry about your daughter quite so much!
Good luck. Critters and babies together are fun, but they do pose a bit more of a challenge!