Chapter 1

Luke brings Sanjay home at Christmas to meet his family and friends. He was hoping for a normal family Christmas until he discovers the death of his mother upon arriving home. He now has to take full responsibility of his little sister Sky. What's more, Sarah Jane has a secret and has left a video message for them, with one final task she wants them to complete in her memory.
The story of loss, love and Zygons.
And how does the Doctor fit into all of this?