Don't know about the adoption theory. I have spotted 2 "orphan" fawns scouting this year. At 1st I thought they were twins followng 1 doe around the field. But they had been in the field when I got there to scout. Each nite after for 4-5 I was there early.
Smallest fawn came out from a heavy bedded area. Hopped around while eating a bit here and there. Then the doe prolly 150 yds away no where near the fawn entrance, which the fawn scooted back into the tall weeds out of sight. A few minutes later he reappeared. Then anoth 10 minutes or so later the 2nd fawn enters the field where the 1st did. No where near the does entry point.
The fawn stayed relatively close to the doe, but if something spooked them, (4 wheeler 1 nite, tractor another) the fawns went to the weeds and the doe to the woods 100yds away. There is a doe/fawn pair in this area but they stay together always. Their bedding down at the corner in between the solo doe and 2 fawns entrance points.
But personally back to main topic. I feel by this time, 15th openner in Mo. Most fawns are losing the spots (My area anyway) and feed same as mama. Meat goes in the freezer. So mama goes down.