Balong Stutters

My son is back to his stuttering ways again...he's 5 years old, he's supposed to overcome it by now, at least that's what statistics say. He had a major stuttering problem when he was around 3 but somehow he got over it when he was around 4.
He's 5 years, 5 months and 7 days old as of this moment and he is stuttering again. I used to find it funny and cute but somehow it's not anymore. My mother still think it's funny, he teases him all the time. I try to tell not to do it because it may cause a lifetime of damaging effect on him but she won't believe me, "you just don't ridicule a child, it's not right, no matter how innocent you might think it is," I always tell her but we'll just end up arguing so I just tell my child to ignore whatever Lola says.
I don't sing in public, I don't dance ever because of her, she used to laugh at me all the time when I was a kid. You know how kids are...they just love to sing and dance and I used to do that when I was around 6 or 7 believe it or not, she would compliment my sister and she would laugh and ridicule me, I told her that a couple of time before but she couldn't or wouldn't believe that such innocent(?) remark(s) could totally wreck my personality after all these years. It's not her fault, at least she didn't know that it's not right to ridicule a child or make some harsh comments about a child, they, along with other parents at the time, weren't aware about the E.Q. and everything else that relates to a child's emotion and what it may do to him/her in the future. Who and what we are today is the result of our childhood, I tell her over and over but she won't believe me, "Uhh umm...adula amin," is her reply everytime, she's Chinese-Ilocano so sometimes she speaks Fookien and sometimes Ilocano. I don't hate my mother, I love her with all my heart pero kasi naman eh, bakit ba naman sya masyadong asar minsan!
But that's another story.
I'm not sure what could've triggered his stuttering, if at all it is triggered by something. I'm planning to visit his doctor one of these days, I'm really really worried, most of the time my friends would laugh at me for being so paranoid all the time, I worry too much for my kids, I'm pretty sure they're gonna laugh once they read this, I'm sure this is funny...I imagine one them saying "she's having an episode again." Hehe...laugh all you want, guys!
His typical sentence is like this:
"Nanay, nanay, nanay, nanay sabi ni teacher, 'wag daw a-a-a-absent tomorrow."
"N-n-n-n-nay, nag-away kami ni Chloe. K-k-k-k-k-asi sambahe sya eh, di ko na sya mahal"
He finds it hard to start a sencence, it's the first word that he finds most difficult to say but sometimes he also stuttters in mid-sentence. Sometimes I want hit his head so the word will come out but I don't, of course. But it can be very very frustrating sometimes.
He'll be graduating this March 27, he couldn't write well but at least he can now write his full name, thank God. His teacher told me that he's a bright kid with a very short attention span. He has very high test scores, I couldn't believe it myself. Di naman siguro autistic?
My mother was hurting her sides laughing because she couldn't believe that Balong will graduate.
"Akalain mong ga-graduate si Balong, hahahaha!!!"
"Alam mo buti na lang medyo may itsura yang anak mo, kung nagkataon...hahaha! Limang taon na di pa nakakabasa!!! Di parehas ni Gillian."
ASAR DI BA? Pero mahal ko nanay ko ha!