Support bubble between tier 4 and tier 2

[ElizabethinherGermanGarden]

I am my dad's support bubble (my mum has Alzheimer's and needs constant care; he needs the relief of another person to talk to and hug). We all live in the same village, about 15 mins walk apart, but we are either side of the dividing line between districts so I am now in tier 4 while they are in tier 2. If they walk the dog to the village centre and seashore between our houses, they will be entering tier 4 - the local shops etc for dad are in tier 4. If I go to his house, I'll be leaving my tier 4 area.

I can't find explicit guidance on this, but my thinking is that we can continue to be a support bubble, but that dad will have to behave as if he's in tier 4 if he's in a bubble with me. That will be less hassle for him all round, I think - they don't go out much except to the local shops etc.

Having said that, as tier 2 people, they could have my sister for Christmas Day. I'm all torn.

The support bubble can definitely continue.

And I don’t think that means he has to behave as if he’s in tier 4, he should be able to have your sister for Christmas. Making it law that those who bubble with people in tier 4 have to act like they’re in tier 4 would be a nightmare.
Obviously I’m talking about the law, not guidance, and living so close to a tier 4 area should clearly be taken into account when deciding what to do (not just for Christmas but everything).

Thank you. They go out very little anyway, and mainly when they do, they go out to places in the nearby tier 4 area rather than up the long road to the nearest tier 2 town. It's just the sister-factor that's worrying me.