We got a double stroller.
Kiddo still loves riding in the stroller - most of the time. This is the only way the "family" can go for a "run". Eventually. I've been doing as much walking as possible, but it will be some time before I can work up to running... and the step AFTER that will be running while pushing the double stroller!
On a few occasions - with Kiddo in daycare - I've taken just Baby G in the stroller. I think if Kiddo knew, a war would be raged in our house!
For now, he's accepted that he has to share with Baby G. Either way, it's a couple more years we'll be using a stroller of some kind - particularly with the little one!