"I scratch their back, they scratch you."

Animal Friend

Enchant creature
Enchanted creature has "Whenever this creature attacks, create a 1/1 green Squirrel creature token. Put a +1/+1 counter on that token for each Aura and Equipment attached to this creature other than Animal Friend."

Fallout

The token will enter the battlefield and then have counters put on it. In most cases, the game will see a 1/1 creature entering the battlefield for the purposes of any abilities that may trigger, such as the first ability of Overseer of Vault 76.