Commercial for "Children's Benadryl" was just on....?

and my question is.......they took all the kids' "cold medicines" off the market because of children ODing on them, etc. (my kids grew up just fine having them but whatever) -- what is the difference to have allergy meds available but not cold meds? Just curious -- I have grandbabies now....mine are grown so it's not an issue for me personally -- just a curiousity. I know people can OD on benadryl also.