My 5 year old accidently droped his ds in dogs food bowl

Make sure that the device is off (take out the battery ASAP if possible). and let it dry for a few days. If you can take it apart, get out any water, and leave is open to dry that would be best. there are ways to make it dry faster/better like putting it in a container with a thing of damp rid or any other desiccant (don't let the desiccant get into the device though,desiccant can suck the moisture out of the air which will draw more water from the device into the air and so on)