I have be lisping since I be roughly speaking 4 , How can it be cured as an developed ?

Kids had other made fun of me because I didn't say my (S's ) & ( C's ) the right channel. I always kept quit so kids won;t produce fum of me. How can it be cure with out the speech Therapy at home ?I have be lisping since I be roughly speaking 4 , How can it be cured as an developed ?
Why cure it? I come up with it is cute. There is a lady on tv that does it and an anchorman on a communication show that does it. It isnt anything to be ashamed of. Kids are just cruel.
Kids can be soooooooo throaty and cruel, I'm a teen and got made fun of at arts school because I have a bulk problem..Only thing I guest you can do is the Speech Therapy stuff!
I choice you all the best!