LOL, I grew up in a family of 6 children, all of us close together in age and I do remember my mom saying a few times: "A little dirt ain't gonna kill you" but that was due to us playing in a dirt pile with a pail and shovel or making mud pies after a rain shower.
We never had birdbaths in the yard when I was a youngster but as an adult I learned about bacteria issues regarding birds when my husband and I had pet birds over the years and I learned more when I began planting a garden for attracting birds and placing bird feeders and water dishes/birdbaths in the garden for their use.
When it comes to the bacteria spread by birdbaths, I'd be very wary of allowing a child to play in the water which is more than likely contaminated by bird droppings unless the neighbor cleans it daily. Birdbaths should be cleaned regularly to prevent the spread of diseases from bird to bird but there are also diseases that can be spread from bird to human such as bacteria that causes salmonella and e-coli, among others.
An article containing information regarding the subject:
http://vetextension.wsu.edu/wp...
