This may not always be easy, as has been stated above; the behaviour may have started in reaction to stress, and has become compulsive behaviour. (petsmagazine.com.sg)
These are normal reactions to the stress of a new sibling that require tolerance rather than punishment. (mayoclinic.org)
The body's natural reaction to stress is to release this hormone, which is created in the adrenal glands. (discovermagazine.com)