DEAR ABBY: I generally have an excellent relationship with my 14-year-old granddaughter. However, she thinks it’s funny to tell me outrageous lies with a straight face to see if she can get me to believe them. She laughs when I am unsure of whether she is telling the truth.

Once she told me her family was going to Hawaii for a month (she lives with her father rather than with my daughter, so I’m not privy to his plans). Another time, she jerked her arms around and said she has “tics.” When I asked what she was talking about, she announced she had Tourette’s syndrome.

Both were untrue. I had epilepsy as a teenager, so I’m especially sensitive about a grandchild developing a neurological condition at the age I was. It felt like a cruel thing for her to do to me, and I was not amused. When I told her I didn’t like it, she giggled and said, “Oh, Grandma!”

I had arranged for her to do weekly yard work for me, but now I’m having second thoughts about having her around that often if she’s going to purposely upset me like that. I sent a text to her mother telling her about it, but received no response indicating she would talk to her daughter about it or have her apologize. What should I do? — HUMORLESS IN IOWA

DEAR HUMORLESS: Try this: Tell your granddaughter you have bought tickets to a Taylor Swift or Harry Styles concert and ask if she would like to go with you. Then, when she reacts, start laughing.

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Dear Abby is written by Abigail Van Buren, also known as Jeanne Phillips, and was founded by her mother, Pauline Phillips. Contact Dear Abby at www.DearAbby.com or P.O. Box 69440, Los Angeles, CA 90069.