Hi there, hope you are enjoying BYC!
Thank you for sharing this. Glad your daughter will be okay!
NO, ALL chickens do NOT carry salmonella though they CAN and that's why I buy only from NPIP tested flocks as they tend to be more stringent about their biosecurity.
https://www.mypetchicken.com/backya...and-why-should-I-purchase-only-from-H350.aspx
Discuss with your supplier possibly switching their practice to only purchase NPIP chicks as well expressing what happened with your daughter and the difference between tested verses non tested flock. Take whatever printed documentation you can leave for them to review. Find the most convincing and easy to understand to share with them. Their initial thought MAY have been an acceptable answer but once you share YOUR new information with them.. they will surely want to take steps to protect their community that supports them! If one of my LFS purchases local birds from untested flocks.. I shop elsewhere.. I won't even buy hatchery chicks that were in the same room as too many diseases can pass too easily.
https://www.nationalchickencouncil.org/questions-answers-about-salmonella/
https://www.revealnews.org/article/10-things-to-know-before-you-eat-your-next-chicken-dinner/
https://www.wideopenpets.com/5-ways-prevent-salmonella-backyard-chickens/
https://www.chickencheck.in/faq/salmonella-cause-prevention/
Hope these links give interesting reads instead of being mumble jumble..
Yes, I would take those chicks back and NOT add them to my flock. How did they do the testing on the chick and how much did that cost you? Also, please add you general location to your profile as it will help folks make their most relevant suggestion possible at a glance.. and it will correlate things like the question I asked about cost with your location.
Also.. please note you say "healthy looking"... lot's of healthy looking things can be carrying harmful bacteria, viruses, protozoa.. that isn't effecting them kept in check by their own immune system... yet shedding harmful amounts of it to unsuspecting victims.. seeing how all these things works really gives a much clearer understanding of this Covid pandemic.. and good animal husbandry practices like not over crowding. Our actual perception is limited to what we see, smell, hear, touch, or taste. But our world is so much broader than that!