I just got back from a walk with my 2 daughters, 3.5 months and almost 2 years, and our very large laboradoodle. I'm not sure if you know what one of those looks is, but he's a mix between a standard poodle (yes, the big ones) and a laborador; so picture a lab with long legs and a perm. So anyway, up until this point, I was using a double side by side combi stroller that I had gotten on craigslist for our nightly walks. Don't get me wrong... I love this stroller (and the price was perfect), but it's not ideal for our nightly walks because the sidewalk is littered with uneven cracks and lifted edges and trying to get those tiny wheels over the curb with my 2 year old leaning forward is just about impossible without giving her whiplash.
Earlier today I brought out my Ergo baby sport to see if my youngest had the head control for it (they say not to use it without the infant insert until 4 months), but it seemed to work well. Heck, she even fell asleep in it. So for this evenings walk I decided to put her in my carrier, but Charlotte, my oldest, in her brand new Radio Flyer wagon that grandma and grandpa gave her for Christmas, and leave the dog on his gentle leader leash. I have to say that it was one of the best walks we've had in a while. Jillie was happy, Charlotte had a ball going back and forth between the seats on the wagon; the only one who wasn't thrilled was the dog who was kept on his short leash, but with 2 kids he's lucky he's getting a walk as it is.
I bought my Ergo carrier when Charlotte was a few months old after a college friend recomended and thought it was pretty neat. Although with 2 kids, this thing is fantastic! Now that my youngest is old enough for it, no more squeezing the double stroller through small doorways, no more ring sling (which worked ok for me), and no more HotSling (which I was NOT a fan of).