My little copycat

Oliver is turning into quite the copycat... he likes to repeat the words we say, makes his own coughing noises when people cough, and for the last two days has started something new he learned from me and Gabriella. Check out the picture and see if you can figure out what he is doing. Here are some hints... when I asked him what he was doing he told me "A Bop hungey" (Baby Bop is "A Bop") . So I asked what he was feeding her and he said "milk." But his milk comes from his "outie" belly button! Pretty amazing!