One of the things I’ve always marveled at is how good Mac is about just playing by himself. Given that I basically never put him down for the first 6 months of his life (how did that kid ever learn to crawl?!?!), it’s a miracle that he has any notion of how to play independently. But he’s always been great about building with blocks or boxes or balls or whatever.
As much as I love sitting with him on my lap and playing with him, one of my favorite things is sitting quietly while I observe his imagination at work. Playing by his side or watching him play from afar, I never stop being awed by how awesome my kid is.