Does anybody know this tree/shrub

Does anybody know this tree/shrub

Observation - Does anybody know this tree/shrub - UK and Ireland. Description: This tree(?) has appeared over the winter as far as I can recall. The pot has been living near a pyracanthus but I don't think it is one.

This tree(?) has appeared over the winter as far as I can recall. The pot has been living near a pyracanthus but I don't think it is one.