Nearly all body safety literature says a child should tell a “trusted adult” if something happens to them. But if they haven’t identified those adults and developed trusting relationships with them, they won't know who to talk to.
You might think, “well, they can tell me…”, but imagine the abuser specifically threatened your child not to tell you, or the abuser is your partner or parent.
On the less extreme end, many kids simply don't tell their parents if they’ve experienced something that feels wrong -- maybe they're worried they'll lose their parents' love or trust.
Identifying trusted adults other than parents gives a child options and makes it more likely that they will (eventually) tell if something happened to them.
Also, because you and your child will invite these adults to be in your child’s safety circle and you explain what your expectations are, they will know how to take action if your child does report something.
Finally, it’s possible that an adult your child trusts is a potential abuser (93% of abusers are known to the child*). Inviting them into the safety circle and explaining your expectations may actually deter abuse: it lets the person know that you are aware of CSA risks, that you are watching, and that you’ve surrounded your child with other adults who are watching too.
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