I apologize that no one has responded to your question sooner. Different experts come online at various times. I just came online and saw your question. My name is ***** ***** I’m a biologist with a special interest in birds. I'm so sorry for the loss of your parakeet.
Your remaining bird will need some time to process its grief. At first, one of the best ways to help is with human attention. You could spend some time each day talking quietly to him from outside the cage. If the cage isn't already in a room where you spend a lot of time, you could move it to such a room. The activity will distract him, and give him something to watch. When no one is home, try putting the cage near a window. One with a view of a bird feeder would be ideal. You can also quietly play a radio set to a classical music station.
After some time passes, your remaining bird probably would enjoy a companion, but don't just introduce a new bird directly into the cage. A young bird is best, ***** ***** which sex you choose. The first step is a quarantine period of at least ten days to make sure the new bird is not sick. They should be in separate rooms during this time. You'll need a second cage for the new bird. It can be a small one because it's going to be temporary. After the quarantine period, set the cage with the young parakeet in it next to your present cage. Let the birds take a week or so to get to know each other. When they seem to like each other, let them meet face-to-face outside of both cages. After they've done well with this a few times, they can begin to share a cage.
Whether you decide to get a second bird is up to you. There is no right or wrong decision. Many parakeets live quite happily with only human companionship, but those which spend a lot of time alone do better with a friend. If you have more questions, let me know in a REPLY. I hope that whatever you decide to do, it will work out well.
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