Reblogging on Tumblr is similar to re-tweeting: A post is reblogged from one tumblog to another.
Teens even broadcast themselves sleeping, which illustrates the urge to share all aspects of life, even intimate moments, publicly -- and potentially with strangers.
Teens often broadcast from their bedrooms, which often have personal information visible, and they sometimes will share a phone number or an email address with viewers, not knowing who's really watching.
It's easy for someone to take a screenshot while in a chat and share it with whomever they want.
Even if there's no offline contact, however, without age verification, teens are connecting with people they don't know who may be much older.