You control who has your Skylight email address, so only give it to people who you want to send photos to your Skylight.
You can set up your frame as 'Private', which means you will have to approve each person that sends photos to your Skylight, or 'Public', which means anyone with your Skylight email address can send photos to it.
To change your privacy settings, please follow the instructions in How do I change my privacy settings?.
You have the ability to block specific offending email addresses, but we are able, upon request, to assist with this process (Blacklisting).