Quote from Barney in The Fortress
Future Ted: [v.o.] In the spring of 2013, Barney and Robin were just weeks away from tying the knot. But there were still some pretty big issues they hadn't agreed on. Robin: Adoption. Barney: I don't know. Robin: It's the only thing that makes sense. I can't... I can't believe you're not open to it. Barney: Okay. Let's try it. Nope, it doesn't work with 27 down.