When an infant is plaintiff, a guardian ad litem may be appointed upon the application of the infant if the infant is at least fourteen years of age. If the infant is under that age, the application may be made by the infant’s guardian or conservator, if the infant has one, or by a relative or friend of the infant. If the application is made by a relative or friend, notice thereof must be given to the guardian or conservator, if there is one, and if not, then to the person with whom the infant resides.