A complex sentence contains one independent clause and at least one dependent clause. Here, in your example, there are two simple independent clauses which you need to merge using a dependent adjectival clause in order to make one complex sentence. Here is how to do it:
The boy <u>who wore a green coat</u><u /> carried his sister home.
Answer:
My favorite toy as a child was a Finona plusie. I loved this toy because at the time Shrek was my favorite movie. Her hair was braid with yarn. Her dress was green and velvet with golden details on the torso. She had a crown attached to her head. This toy was given to me by my mother.
