Are you able to calculate how many jr.members were born from yesterday to today and from who were born?
For example, if a person gave the birth to 10 or 20 or 30 Jr.Members can starts to be suspicious!
Are you talking location wise, or IP?
There's really no way to determine "from who were born" unless the accounts are linked together (using a script of some sort)
Admins may have more information, but this would be difficult to achieve w/ public information.