Bobby decided to go see how Dean was dealing with baby Sammy and maybe lend a hand. He decided against ringing the bell just in case for some reason baby Sammy was still sleeping and Dean was getting some much needed rest.
Hearing commotion from the kitchen he headed to the back. "Mornin' everybody. Thought I'd come and lend a hand if need be. Guess there's plenty of hands around. Che? Did I hear coffee?"
Looking around he saw... Sam wasn't no baby anymore. He was a toddler. "Sammy! You got big!" He wasn't sure on whether or not the toddler would even recognize him but it was kinda amusing to Bobby to see a sight that he'd never see again.