People wanted to share information in a more private setting. We originally started the group as a proselyting mission to spread EL, and while many want to do that, they also don't feel comfortable sharing photos of their kids, and they don't want posts that could be seen as bragging showing up on their personal friend's newsfeeds. I didn't know it would do that. The open group is bigger and is doing well, but the closed group has EXPLODED with activity. They both serve a useful purpose.
More on what open vs closed means here:
https://www.facebook.com/help/220336891328465/#What-are-the-privacy-options-for-groups 
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