A couple of weeks ago it occurred to me that Eli could probably walk. I based this on the fact that he was spending most of his time on his feet, either cruising around the furniture or standing in the middle of the room playing with his toys.
So one Sunday afternoon, after we got home from his friend Milly's 1st birthday party, I watched him standing there with a ball in each hand giggling. So I knelt down 4 feet away and asked him to walk to me. He stood there giggling for awhile, and then he cheerfully picked up his foot and moved it towards me, and took four confident steps in my direction, before flinging his arms around my neck with a giggle.
A week after his first steps we're at Samantha's 1st birthday party. Suddenly, he takes off towards her! He walked a few times that day, apparently inspired by all of the exciting things and people to see. Now he seems inclined some days to walk a lot, others not. To him it's an exciting novelty rather than a mode of transportation. He's always crawled so quickly he has no need of an alternate transport method.
It's one of those milestones that prior to having kids I thought would matter, but now kind of doesn't. They learn these things so gradually over time that there is no definitive milestone, just constant learning every day.