Have they laid the second egg yet? If you move them after the first egg and lock them in the hen will usually lay the the second egg in the bowl and then they'll sit them. I haven't had any success at moving two eggs even a few inches and they've come off them.
This year, for the first time, two of my pairs laid in the same bowl as the youngsters, this was despite there being a second bowl in the nest box for them!
I tried moving the babies over into the other bowl but they kept going back in with the eggs! The eggs would have got broken so the babies had to go on the loft floor! If you do put babies down on the floor always put down as many as you can at once. That way the cocks don't knock them about.