For Children

Don't need advice :

For girls no secret : a doll or a baby doll would be enough. Also the dinette or a stuffed animal. If the child asks for a pony, do not worry! There are rocking ponies not very expensive in toy stores :) A kitten it would also make a good company. (you can get one free with your friends if they have an effect.)
 
For boys: their favorite figurines will make him great pleasure. Spiderman and Wolverine are among the favorite hero of 4-8 years for others it is rather figures of wrestlers such as John Cena, Randy Orton and The Undertaker. The boys really like dogs and cars too. A puppy from a breed that loves family and children (who are patient with them) is preferable. A Golden Retriever or Labrador are generally nicer to children, like Saint Bernards :) (it must be used quickly to be clean and wise, or it may cause some damage to furniture and make the house dirty if he's not used well enough to do his business outside.)