Related Clues:

• Tots' attention-getters, perhaps
• Tots give them to get attention
• Liner guides
• Actions on heartstrings and pant legs
• Port pushers
• Towboats
• Water towers?
• Tows
• Actions on heartstrings
• Harbor workhorses
• Actions on shirtsleeves
• Harbor vessels
• They're diesel-powered
• Port pullers
• Canal boats