I’m 19

So I’ve been wanting to get a tattoo so bad in memory of my niece who passed during still-birth, short story it’s the hospitals fault so we’re suing them. Anyways, I’ve been wanting tattoo but my mom isn’t very big fan on tattoos and i love her and respect her so much but i just really really want a tattoo so bad and i’m not sure if i should just go ahead and get it myself since i’m an adult now but i live under her roof for right now. I almost got her convinced to let me get one but she said only small ones ugh lol help