As a nanny, I don't get to see a lot of firsts. Were I watching infants and babies I would, probably; with toddlers, though, firsts come in the form of places and events - first dentist visit (which I actually was at), first plane trip, first time at the beach.
Today, I watched Lilly take her first pony ride. V and I took them to an amazing park/farm/playground, with pony and wagon rides, a petting zoo, a giant dairy barn converted into a playplace (which, yes, V and I took just as much advantage of as the kids). Lilly pet the pony, and when I asked her if she wanted a ride, she said yes. When I asked Patrick, he said, "I don't like riding the horses." As if he's ever tried.
It was one of those days that didn't feel like work; a big part of that was having V with me. It was just us out with our kids on a mostly-pretty Saturday, watching them spazz and Lilly run three different directions in her excitement.