Photoshop composition

I need you to merge two people and a dog into one picture, as if they were posing together. I have hundreds of picture of the 3 characters, so there is plenty to choose from. The final effect should look as if the 3 of them were posing together when the picture was taken.
This is not a commercial assignment, just a personal project. I would print and frame the resulting image as a gift for a friend. I would need the final work to be received no later than Dec 21st.