Thanks to everyone that has responded. I am definately going to breed the male and female together next year to see if it will happen again. I bet / hope that they will give me twins again next year.

I wonder if it is the male that is causing the twins, or the female, or both. I do not know anything about twins. I bred the spider to two other normal females. The first clutch did not have any twins. This one had two sets. Im still waiting on the last clutch, which is eight eggs, so hopefully I will get some twins in that one. If there are then I know its my male that is causing the twins.

They are awsome looking. I just can't stop peeking inside the incubator.