Re: At what age/ weight did you stop wearing your baby?
Just weighing in with my opinion. I wore all of my kids when I had the opportunity. With my daughter we had one of the Baby Bjorn carriers and that didn't last us long. I only ended up wearing her until she was about 3 months, then I started carrying her because it was just easier. I had a Moby with my first son, and I wore him until summer (in Texas) when it got too hot. I wore him a couple more times when fall and winter rolled around again, but he wasn't interested. Our third child I wore pretty regularly (well, no, I should be fair, Daddy did because he preferred Daddy wear him) until he was a little over a year old, but summer kind of did that in and he became more interested in walking. I'm guessing it's pretty normal for a child to stop being interested in being worn if they've had to take a break from it and got used to something else. With our youngest I plan to wear him for as long as possible, but I'm going to be getting an Ergo because the BabyHawk we have just isn't working out for me. It's great for dad, but I have back problems with it. I'm hoping that's going to extend our baby-wearing because I've heard good things about Ergos in the heat and I've heard from other mamas that they're better for your back.
That being said, it looks like you'll have some more little ones coming your way, so what's the harm in holding on to one? That's why we held on to our Moby (though I never use it, my partner loves it!) and the BabyHawk. We weren't even sure we wanted to have another one, but we wanted to hold on to them just in case. The way we saw it, we could always part with them later should we not have need for them again. We kept both because we each had our favorite. We kept our ring sling too, but that was largely because the kids liked playing with it, so I didn't see the harm in it.
I'd say your best bet is to keep one of them and sell the other. That way you have one on hand should you want it with your adopted child or any future baby. If it works out you can always pick up another one later, but then you won't have two to hold on to until that point.