Part one- the attack of the nine tails.

Sage of six paths was the last person to have all the summoning animals. Naruto saw an ANBU summon a dog at a young age and copied the hand movements. He was summoned to the land of elders where all the elder summons gather.
On the night of his birth his two siblings were born then the nine tails was extracted from kushina. While she was passed out Naruto was born. The wife of the third sealed the nine tails into the three siblings. Naruto got the soul and 5 tails. His siblings each only got 2 tails. He was left behind while his parents left with his siblings.

Will update this description as I go a long
I will say this once I have never and never will own Naruto.