Is it common for a three year old female to get bladder infection

What do you mean by common?

Can a 3 year old get a bladder infection? Yes. Human beings of any age can and do get bladder infections.

Why are you asking?

Just want to add. If you have a three year old, and she's getting numerous bladder infections, it could be because she's not wiping her bum properly after going to the toilet.

One of the most common reasons for a bladder infection are bacteria from the bowel which can spread and enter the urinary tract.