wanted to know if in your icloud email account, can you set up a rule to let only emails from specific addresses (your contacts) through? I didn't see this as a preset rule in the iCloud/mail online interface.
What problem are you trying to solve? iCloud already does pretty decent SPAM filtering. If it's a SPAM issue, just make sure you mark messages as SPAM before you delete them.
You could set a filter to highlight specific contacts if you want to make sure you look at those messages first.
wanted to know if in your icloud email account, can you set up a rule to let only emails from specific addresses (your contacts) through? I didn't see this as a preset rule in the iCloud/mail online interface.
Yes, but that is not going to work on the iPad. That Mail rule will only filter the mail as it comes into that Mac. It is not server side filtering and will not restrict Mail going to the iPad like you want.
You might be better off setting up a GMail account for the kid. You could setup server side filter to only allow mail from people you list and also copy you on the messages so you can monitor things if you like.
Ahh this is a very good reason for what you want to do. May I suggest you provide iCloud feedback to Apple explaining what you want and why, do specifically that it's to protect a child from unauthorized email contact.