This is a difficult question to answer definitively. Each situation is unique. Decisions are made based on each child, their family and the dog.
International standards suggest a two-year training period prior to service dog certification. This includes initial socialization of the puppy followed by basic obedience and public access training that accompanies the scent training. Ongoing collaboration with the trainer and the family is essential. The family must keep a training log, provided by the trainer, while the dog is in the family home. This will help to identify training progress and bonding with the youth.