Text-based adventure game
(1) For variable and function names, check_cave (underscore) rather than checkCave (camelcase) are standard in python.

(2) The line def chooseCave needs to be unindented

(3) Your main game loop could probably be neatened up:

while True:
    display_intro()
    check_cave(choose_cave())
    print("Would you like to play again? (yes or no)")
    if input() not in ('yes', 'y'):
        break


(4) conventionally you should put the main game loop in a function called main() and add

if __name__ == "__main__":
    main()


at the end.

(5) More a matter of taste, but I'd find it more elegant to write choose_cave like this:

def choose_cave():
    while True:
        print("Which cave will you choose? (1 or 2)")
        cave = input()
        if cave in ('1', '2'):
            return cave