after feb 12 "reasonable testing" even if that means "reasonable belief your items are safe" your items are legal to ship by USPS.
(Not likely to endanger postal workers in any case)
for example, if someone takes all my pain pills at once it will probably kill them. However, I can order my medication through the mail, and it's fine.
after the august requirements change... I think our kids items are still not what USPS is worried about. (it's not a bomb, industrial chemicals, or anthrax...)
ASK a your post office though, just to be safe...and maybe enlist them too. (what happens to postal rates if they lose so many of us shipping toys, and baby clothes.)