Add Person to Outdoor Group Photo

I have an outdoor family shot that I’d like to share on social media, but one person missed the moment. I need that person seamlessly composited into the scene so it looks as though they were always there... (Budget: £10 - £20 GBP, Jobs: Adobe Photoshop, After Effects, Animation, Color Grading, Graphic Design, Image Processing, Photo Editing, Photo Retouching, Photoshop, Visual Effects)