Naked babies

Since the upstairs is usually pretty hot, I just let the kids sleep in their diapers. The other night Reese came up to me touching her naked tummy and said what sounded like, "I'm making babies!" I was caught off guard and said "What?" thinking to myself, who taught her this! She repeated again and again it sounded like, "I'm making babies!" I was mortified thinking who could have taught her this or what did she see! Finally, it dawned on me that she was saying "I'm a naked baby!" I asked her if that was what she said and I was so relieved when she said, "Yes!"