Miranda Rights

There is really no such thing as "Miranda Rights". The Miranda Warning came from a USSC decision - Miranda v. Arizona. (For a brief overview look at http://www.bartleby.com/59/14/mirandadecis.html )

For a juvenile the Miranda ruling still appllies but there can be some additional requirements that are applied on a case-by-case basis. If a juvenile is determined to be competent to understand their rights the police can usually question the child by themselves. If they aren't then a parent or legal guardian is normally made aware of them and has to be present when the child is questioned and can normally stop police questioning on behalf of the minor until a lawyer is present.

Each state treats juvenile issues slightly differently. For some info on FL take a look at:
http://www.flabar.org/tfb/TFBConsum.nsf/0/8a66199487dc11a685256b2f006c57ff?OpenDocument