Dear Steven,
I'm also 11 years old, my birthday is on 8th of November. I was happy to get a puppy as a present for my last birthday. I've got a sister/ Her name is Olga. She is younger than me, but we both go to school. I'm in class 5 D and Olga is in 3 A.
Sorry, my mum needs my help that's why I should finish my letter.
With love,
Alex