My 3-and-half-year-old son has Speech delay and possibly disorder!?

I HAVE A THREE YEAR OLD DAUGHTER WHO WAS EVALUATED AT THE AGE OF TWO FOR SPEECH . SHE WAS REFERRED FOR THERAPY RIGHT AWAY BECAUSE SHE DIDNT SPEAK ONE WORD. FOR HER THIRD BIRTHDAY SHE WAS REEVALUATED AND STILL NEEDS THE SERVICES. ALTHOUGH HER FIRST YEAR OF THERAPY WENT GREAT, SHE STILL HAS TROUBLE PRONOUNCING SOME WORDS. LIKE UR SON WE CAN UNDERSTAND HER BECAUSE WE'RE USETO IT BUT OTHER PEOPLE STILL HAVE A HARD TIME UNDERSTANDING HER. I THINK U SHOULD GET HIM EVALUATED FOR SPEECH THERAPY. IT'LL BE THE BEST THING U CAN DO. BELIEVE ME YOU'LL SEE THE DIFFERENCE!! GOOD LUCK!!!!