I had to switch jobs to a lower paying job due to COVID and had to withdraw from my 401K

I had to switch jobs to a lower paying job due to COVID (not being able to handle the intense stress of a workload with a child) and had to withdraw from my 401K. Because I switched jobs towards the later qtr of 2020, the impact isn't so dramatic. 

 

In terms of waving the early withdrew penalty as I took the withdraw in 2020, what proof do I need to show the IRS, other than I physically switch companies via my W2 forms?

 

How do I prove that I now have to take care of a child?