Alum Cave trail will put you on a cool formation, "but" it is about 5 mile RT, if you could get mama up there 9 out of 10 times you can catch a glimps of the Peregrine Falcon that usually nests on the bluff.
What ever you do don't take the fun out of it, short hikes will make it a vacation for everybody.
My family are all moderate hikers, the last trip we all took together my kids were in there mid teens, I got us on a trail that was cool to me and the wife but a little to much for them, "16 miles RT" when one of them said it was too much like work we took a water break and turned around, No need for anyone to be unhappy on a vacation.