I too thought he was bordering in abusive the other night - but again almost through thoughtlessness and childishness than malice. I thought it was really sad how he dismissed he conversation about stir-up Sunday - even if it is a bit weird it's her family tradition, and given how close she was to her Gran previously I could understand her wanting to offer an olive branch by turning up.
She/the family have really painted herself into a corner though because she's so vehemently defensive of Toby in the face of their opposition. Will be interesting to see how long it lasts and what makes her finally kick him out.
Going back to Rob's monthly contact. I think for a baby almost any contact other than daily care-giver is probably pointless. But many children only see, for example, their grandparents once a month (or less). I guess over time Rob will be familiar to Jack. But ime it will take until he's 18months - 2yrs for him to really remember him with this infrequent contact. Will be interesting to see how Rob copes with that - can't see him liking it or really tolerating it. All the more need for professional supervision in my opinion