Definitely separate. We have in right now four little lovebirds. They were all housed in a large cage and both males have sores. The female (mother of the two youngest) was plucking and biting at the oldest male until she caused a large bleeding sore on his back, his previous owner did not know how to deal with this and just left them in together. Now he is being treated with antibiotics because she let it go too long and has caused infection in his system. The female was also pulling out the chest feathers on the younger male but luckily it had not yet resulted in bleeding sores. They are of course all seperated now, but now we have the problem that the male with the sores is not pulling out his own feathers and the vet thinks he may have to be put in a collar until he is completely healed if he won't leave it alone. We go back tomorrow to see what he decides.