Is the children's Benadryl for you or do you have children in the family? If not for children then I'd include adult Benadryl.
If you have children include some children's pain relief such as children's Motrin or such. There was some kind of a shortage on children's pain meds recently so keeping some pre-stocked is a big help.

Also I'd stock some other pain relief besides just acetaminophen. Add in Ibuprofen (Advil and Motrin) and maybe Naproxen (Aleve).
A quick example I found https://www.hss.edu/pediatrics-difference-between-tylenol-advil-aleve.asp
Anti inflamatory can be usefulin some situations.
Some Pedialyte, or drop drop or even Gatorade can be handy.

The dental grab and go kit looks a bit overkill to me. A small bottle of dental pain relief and a temporary filling pack will suffice unless your preparing for post end of the world