If a warden kills a large slime or magma cube, it will not automatically be angry to what it splits into

The bug

If a warden kills a slime or magma cube which is larger than the minimum size, it will not automatically be angry towards the smaller sized copies it splits into, despite them coming from the same mob it just killed. It instead will need to become aggressive to each one of these individually.

How to reproduce

1. Spawn a large slime or large magma cube

2. Spawn a warden

3. Have the warden kill the slime or magma cube

Expected results

Once the warden kills the big slime/magma cube, it would continue to finish off the smaller copies it splits into.

Actual results

It is not immediately aggressive towards these smaller copies.