Evidence
3V0720.02 [joke… knock-knock]: verbally formulated classification based on a single exemplar. 1/12/80) We all sat at table this evening. Either Gretchen and I teased and all of us laughed, Peggy too. I believe I asked her what she laughs about (the joke was one she could not comprehend). Peggy responded, “joke…” and then continued “knock-knock.” …
3V0718.02 Tirades: reappearance as singing (cf. P103-105); talking to Scurry. (1/10/80) Failing earlier to capture Peggy’s tirades mechanically, I’ve been delighted to find this behavior re-emerge. The most striking example appeared as Peggy led Scurry around the house on the leash. She spent considerable time yammering at Scurry as she took her on this inside …