Gimp Question - for the experianced

Hi, I'm trying to find the control in Gimp that will "stretch" a person's photographed smile, to sort of embellish it. It seems CorelDraw and PhotoShop can do it within their standard toolbox, but I cannot see that function.
In PhotoShop it is call "stretch" and in CorelDraw it is a KPG add-in called "goo".
I'm wondering if in Gimp this function exists as a plug-in somewhere.

Thanks.

Right Click to open the menu and go to Select > Stretch

i am not exactly sure what you're looking for but it might help you a little.