Quoting Mrs Leto:" I wouldnt change anything. He is just a little curious which is nomal and no reason to be private. My ... [snip!] ... my boobies lol but its because im still bfing and its sort of fascinating to her. I still also co shower with her sometimes"
Almost 4 yrs of BF'ing her? Woo! Go you!!
OP DS co-showers with me and recently he started to notice we have different private areas. He looks at me, says "Eeew mama!" and then goes on about playing with his bath toys. He doesn't understand, he is just curious. If you are still comfy with co-showering then keep it up! Don't let your mother try to parent your LO. You are doing nothing wrong. Co-showering should stop when one of you starts getting uncomfortable.