It's depends on the kids situation. Last time, When my son was 3.5 years old, he also get 肺炎, but the doctor said he look like ok (eat, drink and play), even he got fever around 104........ just tell us pay attention at home, if anything happen, just call him and sent him to hospital. So, finally, my son just stay at home and recover after 1.5 week.
But the kids too young, e.g. baby... I think stay at hospital is better la