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Most definitely. This article will help: https://www.gardeningknowhow.com/ornamental/trees/weeping-cherry/pruning-weeping-cherry.htm

You can try treating the area with a fungicide. The best offense for canker is a good defense - this means making sure the tree is as healthy as possible. Make sure the tree is getting enough water and nutrients and is pest free. A healthy tree can fight of the infection better. This article will also help:
https://www.gardeningknowhow.com/ornamental/trees/tgen/cankers-on-trees.htm

Grafting is when two different trees have been joined together. If your tree has been grafted, the grafting scar will be right below the place where the branches start. It will look like a slightly raised ring around the trunk.

There are a few pests it could be. I would treat the tree with a pesticide. I personally like neem oil because it is systemic and will protect the whole tree even if you can't get to the whole tree.

This should be removed. Your tree is a grafted weeping cherry and the branch that is growing upwards is a branch growing from the rootstock, rather than the weeping tree scion. It is best to remove it to discourage future upward growth.

Here is more information:
https://www.gardeningknowhow.com/ornamental/trees/weeping-cherry/pruning-weeping-cherry.htm

Sounds like your tree may be in need of some pruning at the top to remove the older, unproductive growth. This article should help: https://www.gardeningknowhow.com/ornamental/trees/weeping-cherry/pruning-weeping-cherry.htm