Can members of a closed Facebook group invite other members?

[Guy]

I have two Facebook-related questions:

1. I started a Facebook group for my large extended family. I set it to "closed" to keep spammers and non-family members out. My question is this: Can already-accepted members invite other people to join the group? I would like for family members that I'm not already "friends" with to be able to be suggested as a member.

2. One family member of mine that hasn't yet joined this group (but was invited) was able to view a picture that I uploaded. How can this be if I set the group to "closed"? Are invited members able to view pictures and discussions without having joined the group yet?
I'm not seeing the setting you speak of...