Come up with a custom background for DnD 5e. It should follow the general template for custom backgrounds, featuring backstory (one paragraph), proficiency in two skills, any two combinations of tool proficiencies & languages, starting equipment, and a special feature.
Background: Loyal Pupper

Backstory: You used to be the pet puppy of a noble child. The two of you grew up together, almost inseparable. And when the child grew up to be a powerful wizard, and you grew too old to join them on their adventures, the child cast a True Polymorph spell to turn you into a human. Unfortunately, tragedy struck during a battle with an evil dragon, and your friend sacrificed their life to save you and the villagers. Now you continue to perform good deeds and help others as a way to honor your fallen friend. 

Skill Proficiencies: Investigation, Survival
Languages: Common, Beast Speech
Equipment: A puppy collar studded with jewels, a set of noble clothes, a burnt and tattered wizard's book, and a pouch containing 20g.

Feature: Animal Companionship

As someone who has experienced life as both a beast and a human, you have a natural affinity for gaining the trust of animals. When performing any sort of animal handling check, you will have an advantage. And when speaking to an animal using beast speech, you will have an advantage on any persuasion checks performed against the animal. When you are in a city, you can also communicate with the stray dogs who live there and obtain information about the city and its inhabitants. 