SIBLING OR NOT?

On the 29th of this month my Duncan will be 7 months old and lately I have noticed that he is getting him self into more trouble than usual. Im not sure if its a boy thing or the fact that his becoming older or if its lonelyness, a friend suggested that I get another Puppy but at the moment my heart breaks when I have to leave Duncan alone imagine me having 2 dogs that I would have to leave behind???? He is way to spoilt as he is our only baby and the only "grand-pup"[You must be registered and logged in to see this image.] , so you can just imagine what all he currently gets right. Need advice do I get another baby or not?? And how if I should how do I convince daddy dearest that Duncan needs a sibling??????[You must be registered and logged in to see this image.]