Q. My husband and I baby-sit for our great-grandsons two days a week to give their father a chance to rest a little more. He doesn't get much sleep since he drives a truck at night and cares for the children during the day, and we don't want him to be too tired when he's behind the wheel.

The 23-month-old -- a really happy boy whom we love so much -- stays with us from 6 a.m. Thursday until 3 p.m. Friday and the 4-month-old stays on Friday. Although I am 72 and my husband is 79, we have a wonderful time reading to the children and walking to the playground with them.

Everything was going well until last Friday, when the older boy turned into a wild person after he got home, crying, screaming, throwing himself on the floor and refusing to bathe, which he had never done before. After that, his mother said he couldn't spend the night anymore because she couldn't work for eight hours, nurse the baby, cook, clean and take care of tantrums, too.

He had gone to bed at 8 o'clock the night before as always, but she thinks he fell apart because he spent the night at our house.

We also want to know how we can get him to eat the right foods. We fix good, nourishing meals for him but if he doesn't like the taste, he stops eating until we give him the things he likes, such as corn, peanut butter on toast, yogurt or French fries.

Although he seems intelligent enough, he just plays with his little cars rather than puzzles, and he can't count, say his ABCs or dress and undress himself. Shouldn't he be doing these things by now?

A. It's great for you to baby-sit but perhaps your granddaughter and her husband need a different kind of help. Ask and you may find out that your granddaughter would rather have one or both of you spend Thursday night at her place so you could also watch the baby and maybe do some laundry or mending while she goes to the movies with her girlfriends. She has almost as many responsibilities as a single parent and she deserves frequent breaks.

Or maybe she'd like to sit down to a civilized meal once a week. You can establish a great tradition by producing this family dinner, but don't expect your granddaughter to lug the children to your place; she's much too tired and busy for that. Instead, roast a chicken or make a big stew and take it to her house along with the salad and the dressing, the bread and butter, the drinks and the dessert. And then wash the dishes and leave the leftovers so the family will have enough food to last a couple of days.

You can't expect to change the eating habits of your great-grandson this year, however, or probably next year either, for 2-year-olds often have smaller appetites than they did when they were 1.

His diet will be better, though, if you serve natural rather than processed cheese and avoid any foods that contain dye, preservatives, high fructose corn syrup or that have a gritty texture. A little child likes a smooth feeling on his tongue.

As for the food, smear peanut butter on slices of an apple or an Asian pear instead of toast or make smoothies by blending some frozen bananas and berries with milk and a little honey. Or serve your great-grandson black beans and rice -- because they make a whole protein -- or homemade hummus or guacamole on chips. All of these foods are tasty and healthful.

Your great-grandson can also roll up chicken and cheese in a wrap or put them between two tortillas for you to turn into a quesadilla, or he can scramble his own egg by stirring it in a bowl and putting it in the microwave while you press the buttons. A child is more likely to eat what he makes than to eat what you make, but nothing can induce him to play with a boring toy -- and any toy is boring if a child can't play with it easily.

That's why some young children like to play with cars, some like to play with blocks and some like to put puzzles together. It all depends on how well they handle these toys.

Most 23-month-olds can't count or say their ABCs, however -- nor is there any reason for them to reach these milestones so soon -- and they usually can't dress or undress themselves, either, but that's okay. Your great-grandson doesn't have to reach every goal faster than anyone else his age.

Questions? Send them to advice@margueritekelly.com or to Box 15310, Washington, D.C. 20003.