My sincere, no nonsense advice..... if you have the means to take care of them, and the time to devote to them, by all means, bring another into your family. You won't regret it. Even though your baby is very attached to you, you'll be amazed at how having two brings happiness to them both, and to you. They will still be attached to YOU, but will have the company and companionship of each other as well.
