I was born hard of hearing (apparently some hairs in my inner ear didn't grow right). They didn't find out until I was 5 years old in school, and I got hearing aids and put in a speech class. I had to learn the R sound (I pronounced it like W), the L sound (I pronounced it similar to a W), the Z sound (I pronounced it like SH), the S sound (I pronounced it like SH), and of course differentiating the CH/SH sounds. Apparently I had learned a lot of sounds wrong, which is why basically only my sister could really understand what I was saying most of the time.