This has been going on for at least a month now, but both kids can easily open door knobs. For a while, Vivienne was too short and Miles just had not figured it out. But now, they both can easily open doors. While this is an interesting development to note, I have to say that it's kind of frustrating that they can open closets and rooms that we would rather they not get into.
So far they haven't gone into the extra bedroom upstairs that contains their Christmas presents. Let's just hope it stays that way for another 3 weeks or so!