You may need to enlarge this to see what I'm talking about, but the Bramley above is all ONE tree.
However, this year it has decided to do things as TWO trees, by dividing itself in half. The half on the right is covered with flower, and will no doubt bear masses of fruit. And the other half, on the left, has next to nothing.
I can see trouble ahead. Two trees divided by a single trunk. Siamese trees. Winners and losers. Haves and have-nots. Yes, definitely troubled times ahead.
p.s. Amazing; my birds are still there!