These were designed to be able to have easily changable "gems" to match whatever outfit she may want to wear, but it would be easy enough to take this and make any sort of Lego earring style from it.
Step 1: Stuff you'll need
Earring loops (or some other small ring)
Lego blocks depending on what you want the earring to look like
I bought a small variety back of loops for a few other projects. The size of loop you'll want will depend on the looks you want and the size of the block you're connecting to. I used the 1/8" loops for the earrings here.