I have a round face and when I make the mouth without subdivision and add subdivision, I get this little gap in the mouth.cartoon face_1c.blend (451 KB) Hope my attachment is there for you to see, if not let me know and I will try again.
Just bring the Mirror modifier above the subsurf.
That is because you have the mirror modifier under the subsurf modifier.
Click on this :
To bring the mirror modifier on top of the subsurf modifier and the problem will be solved.
edit ; sourvinos was quicker
wonderful…need to remember that…thanks Sanctuary and Sourvinos…