"Girls' toys" tend to focus on appearance and domestic roles, according to University of Indiana psychology professor Judith Elaine Blakemore on the National Association for the Education of Young Children's website. Though some little girls are naturally drawn to these types of toys, many have them foisted upon them by well-meaning adults. If you're most interested in developing the cognitive abilities of an 18-month-old girl you adore, it's best to give gifts that are gender-neutral, although these types of toys can definitely have a feminine flair.
Books for young children introduce them to early reading concepts and can improve vocabulary. A series of books by "Bright Baby" offer real-life photos of objects and animals and some of the words that baby is most familiar with. "First 100 Words," for example, has sections on animals, household items and clothing. The little girl might also like "First 100 Animals," which follows a similar format, but focuses solely on animals. Books that have lift-the-flaps can also capture the attention of an 18-month-old. Check out "Peek a Who" by Nina Laden, "Peek a Boo I Love You" by Sandra Magsamen or "Where Is Baby's Belly Button?" by Karen Katz.
A preschool-age child might be disappointed to receive clothes instead of toys, but an 18-month-old baby probably won't care. If you've heard the parents lamenting the piles of toys taking over their home, consider clothing. Since toddlers grow out of their clothes so quickly, the parents will be grateful. Remember that toddlers can sometimes have difficulty walking, so short skirts or pants are more practical than long dresses. However, you may also want to consider dress-up clothes, like tutus or fairy wings, if the little one in question is so inclined.
Little girls don't always prefer quiet activities. Choosing toys that can get them active is good for building gross motor skills, as well as getting some of that energy out. Look for ride-on toys, tricycles and the classic ball. All of these types of toys come in "girl-friendly" (pink) versions, though you should ask the parents what colors or characters the girl is familiar with and go with that.
Toys that serve a variety of purposes build fine motor skills and imagination at the same time, according to Professor Blakemore. Blocks and other types of building toys are ideal for this, though you should check the label for age-appropriateness. Some types have pieces that are too small for an 18-month-old. Easy wooden puzzles are also a good choice for this age group. Again, look for a style that matches the little one's interests.