We live in Colorado & fly to NY to visit family.  We keep all Danny’s meds, including the solu-cortef in a first-aid type bag inside his diaper bag.  We tell them before we go through & there hasn’t been a problem; however, I had 2 extra plastic syringes we use for giving him his daily florinef & cortef & that they couldn’t figure out-

Just to be safe, I also carry his current med records, precription labels...

I hope your daughters have a great trip with their grandparents!! It’s really a great state to visit!!

Best wishes!