They can get them removed later in life, but it's a lot more complicated then because the joint has matured. It's akin to amputating a toe and there is a longer recovery period. But if the dew claw keeps getting injured there is a greater chance of infection and damage to bone and removal might be the best solution to the problem.
Your vet should be able to give you a pretty good list of pros and cons for the surgery and if he thinks it's indicated for Lady.
Another option might be to try wrapping her foot with some vet wrap mesh tape--it sticks to itself and stays on pretty well in the woods (we've had to use it on occasion)--or use booties, if you can find some that extend high enough on the leg to cover the dew claw.
"We are--each of us--dying; it's how we live in the meantime that makes the difference."
"It's not what you gather, but what you scatter that tells what kind of life you have lived!"
"Be kinder than necessary, for everyone you meet is fighting some kind of battle."