The tree in my garden

Round the back of my house, in my garden, is a tree.  It is a huge tree, 60 ft intact. It's been here ever since we moved into the house, which was 17 years ago.  When my youngest sister was born, my mum used to put her outside in the shade of the tree to play when it was warm.  My other sister and I used to build obstacle courses around the tree and used it as 'home' or 'base' in multiple games when friends came over. It was home to lots of birds and pesky squirrels.