Every morning and evening I brush my teeth with my Oral B electric toothbrush from Braun. It comes with a timer that automatically starts when you turn the toothbrush on. If you brush your teeth for 2 minutes you are rewarded with a smiley face. If you brush for 2 minutes and 30 seconds you get a big grin. Almost every morning I am in a hurry to go to work and I am tempted to stop after 1 minute, but then I think "just 1 minute more" or "just 30 seconds more" or "just 10 seconds more" and I keep going. Why? Because of the stupid smiley face. If an electronic smiley face can help someone establish a good habit like brushing one's teeth well, think what could you accomplish with some intentional specific personal affirmation.
Why don't you try this? For one week, notice something that your helper does well, then praise them for it. Be specific, be timely (do it promptly) and be personal. "Maria, the bathroom looks spotless. You even made sure we had fresh towels. Thank you." And don't forget to give her a smile. Do that systematically and see what happens. Leave a comment and let us know how it goes.