This topic might have a better name.
Pete (Peri's cousin) or similar, since he doesn't actually appear in this story
Talk about it here.
Pete was a cousin of Peri Brown. In Peri's timeline, when she was inside the Megaptera, he'd only recently begun to walk properly. Peri held a photo of Pete, however it was destroyed by Stafel who wanted her and the Sixth Doctor to be a part of his "framily." (AUDIO: The Song of Megaptera)