Tattoos to commemorate my holocaust survivor grandparents

My grandparents on my dad’s side were Holocaust survivors. Neither had tattoos. My grandma was in a ghetto but was able to escape and worked on a German farm passing as a Polish girl where she endured daily abuse out of fear that they would turn her in. My grandpa was in the camps but by that point they had stopped doing tattoos. So getting tattoos of their numbers is out of the question since my grandma didn’t have a number and my grandpa actively worked to not remember his.

I was thinking of getting two butterflies to represent them since I’ve seen butterflies used as symbolism, but if anyone else knows of other symbolism that is specific for survivors I would love to know. Preferably something wholesome since I want to commemorate their status as survivors, but also the memory of what they meant to me. Nothing that involves blood, pain, or violence. The Shoah and what they endured didn’t define them, they survived and lived long, happy-filled lives.