I think you're adding a second at the right age...mostly because puppies are very accepting of additions.
I have three...spaced approximately a year between each. So Ramsey is almost 3 and my baby, Reggie is 8 months. Ramsey was a year when I got Reese...who she loved immediately, Reese was a year when I got Reggie. When we brought Reggie home....Ramsey quite literally ignored him. Nose in the air...ignored him. Reese followed her lead...cause she's the big sissy...but Reese could not take the temptation not to play with that new puppy and he caved. LOL.
Plus the way I did it....I signed up to potty train for a straight 3 years.
