or attached to love letters!
But, but, but, ……. attaching small pictures to love letters would be so, so, so 1980'ish.
Just upload your preferred picture to your PC, then crop it, resize it and/or purty it all up with the "photo editor" tools ...... and then "copy n' paste" your photo onto a "blank" document page ........ and then "print" out a few sheets of your personalizd stationary and write your correspondence whenever.