Congratulations and welcome, rubynpearlgirl!
I'll echo AOII4ME's suggestion of inCircle, especially for songs and chants. There are a lot of great resources available on the private side of the AOII website as well, so please, use them!
Also, look at prior copies of To Dragma on the AOII website for ideas. There might be another chapter out there doing something that would work well at Rho Beta!
If you haven't already, definitely ask your advisers and your colony specialist these questions. They have some great ideas and loads of AOII contacts out there and they really want to help your chapter develop and grow. It's amazing to think that the things that Rho Beta does now can become a tradition celebrated for decades to come! A signature philanthropic event, an annual campus activity (picnic, passing out hot chocolate, rose sale at Valentine's Day, etc.), even an chapter sisterhood activity--the possibilities are endless when it comes to creating traditions with your sisters.
A few more general comments:
Families are not necessarily an official AOII designation. However as your chapter grows the founding members will eventually take little sisters, and each successive "generation" is considered a family tree.
Many chapters call their big formal dinner dance something along the lines of Red Rose Ball, Red Rose Formal, Roseball, etc. Some chapters hold this in spring and others in fall, probably more based on campus traditions than a strict AOII tradition. Again, the naming is not an official designation but usually involves something related to our beautiful rose.
Roses to you and your sisters!