All kids in our age sleep without pillows? I've been sleeping without …

All kids in our age sleep without pillows? I've been sleeping without a pillow since birth, and I'm always against pillows until 3 years old. I have terrible posture, I'm ashamed, my back hurts. I don't want my child to experience this. It was only when I left my daughter with her parents that she started sleeping on a pillow. It's a good pillow, big, almost all of her body is on it. Now I can't teach her to sleep without it, she only lies down on it otherwise. Or I get so worried about it. What should I do? Should she sleep without a pillow? Or should we remove the pillow altogether?