18 year olds at teen activities?

[robandpam]

I just read the thread about 17 year olds at Adult activities but I have just the opposite problem. My extremely shy nearly 16 year old daughter would probably not do anything without her just turned 18 year old brother. Will he not be able to accompany her to the Loft for Teen activities?

 

[zeldacruiser]

I seem to remember from a thread before our last cruise that 18-year-olds can opt to be teens for the cruise, but if they do so they give up the right to be an adult. Anyone else know for sure?