If this is what you’re after….
I did this in PS but its basic stuff so should be OK in the GIMP.
Open images one and two.
Drag image two onto image one, delete the original image two.
The dragged image will now be called “layer 1“.
With the rectangular marquee tool, select the left-hand side of layer 1, from the edge to include the fluffy toy? to the right of the girls arm.
Edit-Copy-Paste, this puts the selection into a new layer.
This new layer will be called “layer 2”
Drag “layer 1” to the bin/trash, you have done with it.
You now have two layers “layer 2” and background.
Now click on this new layer “layer 2” then go to Edit-Transform-Scale, then holding down the shift key, click on the bottom left of the transform box and push it in to resize the girl hit enter when done. Move into position. I used the fluffy toy and the grass by it, as a register.
Still on “layer 2” create a mask; it’s the white square with a hole in it at the bottom of the layers panel in PS.
Now with black and white selected as fore and background colours respectively, on black with a soft round brush paint away the join correct any mistakes by switching to white and repainting.
Flatten and clone any anomalies.
Done.
Rhodese.
