Lady slippers ?? from my grandma's garden

I saw the name Lady Slippers on a DG discussion and thought of the plants we used to get seed pods from in my grandma's garden. The plant was about 1-2 feet high, in full sun, made smallish pink flowers and the seed pods would burst when thrown on the cement, which is what we'd do as bored children! Round brown seeds inside a little bigger than millet. Anyone know what this old fashioned plant would have been? I've never seen them since. She lived in Metairie, LA--zone 9. Janet