Angry or nosy neighbors, police and social services can get each other caught up in a cycle of escalation that lasts years for some unfortunate families.
This assume some sort of rationality in our legal bureaucracy of course. Unfortunately that doesn’t seem to exist.
The person calling is likely not "lying" about anything. If they believe it is dangerous for a kid to walk in the street, then the answer is a truthful "yes".
These people simply have different worldviews.
If a neighbor makes up details in a report to police, they should be charged with a crime. If the cops are asking "do you think we should investigate" to private citizens, they have abandoned all responsibility as law enforcement.
Imagine crowdsourcing your authority, making the justice system a militia for lazy mobs. Completely upside-down.
After informing them, that unlike childs walking outside, abuse of 911 is a real crime.