They have to have 1000 points before you can invite them.
Find the person you want to add go to their profile and scroll down near the bottom on the right hand side you will see "invite to family"
No, I don't see that space
You just invite them isn't there somewhere you type in their name and they get invited
If you download it, like he said, you would
Download skype and add all the people you play with.
