Possible Clues:

• When new choppers come in, cut centre of tree by half and reduce top of greenery
• Getting new molars, say
• The trouble with baby, perhaps, is that your ball sits on it of course
• Something for the drive for the young that's painful
• Such early troubles could be a mouthful
• Support article identifying problem in infancy
• Object after support for ball is getting ready to bite, perhaps
• Like initial problems produced by article on part of course
• It'd painful for baby
• Process by which baby's incisors etc emerge