Because they have a hard time puckering their lips the right way.
They have a hard time opening up
He was a little horse
Did you make that Fermi?
They wanted to be Soba... I heard that a few days ago and wanted to share it.
She only puckers up for her pacifier.
When their lips move
They're the ones with stretch marks around their lips.
Because dogs can't whistle. (X-post from r/dadjokes)