A Hugga Bunch Hello by Phyllis Fair Cowell, illustrated by Ron C Lipking, 1985.

Bridget likes having her grandmother living with her and the rest of her family. Her grandmother always has time for her and is willing to give her a hug. Her parents are often too busy, her brother thinks hugs are just for girls, and her Aunt Ruth is too fussy.

Then, Aunt Ruth tries to persuade everyone that Bridget’s grandmother should go live in a nursing home. Bridget doesn’t want her grandmother to leave, but she doesn’t know what to do about it.

While she worries, a strange little person steps out of her bedroom mirror. This little person is Huggins, one of the Hugga Bunch. She says that she knows about Bridget’s problem and thinks that she can help. She invites Bridget to come with her to Huggaland.

In Huggaland, the Hugga Bunch take Bridget to see the Book Worm, who may have the solution that Bridget seeks. Both the Hugga Bunch and the Book Worm say that aging can be slowed by affection and “the knowledge that they are needed,” but Bridget thinks that the only solution is to find a way to actually make her grandmother young again.

The Book Worm says that if that’s what Bridget wants, then her grandmother must eat fruit from the Youngberry Tree. Unfortunately, the tree is in the territory of the Mad Queen of Quartz. Although the Hugga Bunch are afraid of her, Bridget is willing to face her for her grandmother’s sake.

Getting there involves going through a few obstacles, including walking sideways on a sideways sidewalk and facing a frightening beast who turns out to be a baby elephant who was under a spell. When they reach the tree, the mad queen takes them prisoner and turns Bridget into a statue. Fortunately, the others manage to break free and save her.

Bridget is happy at being able to bring the Youngberries to her grandmother, but as she passes through the mirror into her room, she accidentally drops them, and they disappear.

Not knowing what else to do, Bridget runs to give her grandmother a hug before she leaves, encouraging her brother to do the same. Bridget’s father wasn’t happy about her grandmother leaving, either, and seeing how much the children will miss her, he declares that she should stay.

This book was made into a made-for-tv movie.  It is currently available on YouTube.  It follows the plot of the book pretty closely.