I actually have 3 of them and the two smaller ones do seem to stick together.
I build this reef with the Gramma Loreto in mind because I love their disposition and I was nervous at first in putting 3 in a relatively small tank, but so far the two do seem to be courting and the other (who is twice the size of the biggest of the other two) checks in on the others occasionally and none of them are showing any aggression to each other.
so far so good, heres a couple more pics....
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