First big bo-bo

So, this happened:

Felix was climbing up the stairs, put his knee on the edge of the step, but only caught the edge of it so his knee slipped down.  He started crying big, awful cries - not the kind where he bumps and is more scared than hurt, but head thrown back, limb-flailing, pushing me away crying.  I saw the cut right away, but it didn't look like much until it started bleeding.  Once it started flowing I could tell how deep it was.  He calmed down really quickly considering how badly it must have hurt, and nursed while John dug through boxes looking for our first aid kit (Murphy's law, right? Of course we'd already packed it).  Then he stopped nursing and started playing in the blood.

We got him bandaged up and he was back to his old self in no time.  I think we can safely say that he handled it more gracefully than I would have.  I almost sent John out for steri strips...being right over his knee I was worried it wouldn't close well.  It scabbed up really well overnight though.

I inspected the stair, and quickly found the offender: a carpet tack sticking straight up in the middle of the front edge of the stair.  I'm actually surprised we went a whole year here without noticing it.  I clipped it off, but I still won't let Felix climb the stairs.  We move in a week anyway.

Question: do you say "bo-bo" [beau beau] or "boo-boo"?  I'm partial to bo-bo myself, but I'm pretty sure I'm in the minority.