I have a pair with 3 babies aged 28 days, 25 days and 18 days old, the hen is wanting to start a second clutch and i do not want her to. She has a eggbum and big poos so i was going to remove her and let the male finish raising the chicks but i am worried that if i move her to a cage with no nestbox that she will decided not to lay the egg due to nowhere to lay and the stress of taking her away from her babies. She is still looking after her babies well.

You don't need to take her out, if she lays more eggs just take them out and trow them away if you don't want her to raise a 2nd clutch.

Just wait until she lays it and then move her. If you move it now she will most likely lay it off of a perch and it will fall to the ground and break.

 

easier just to wait and then move her as soon as she lays.

If you dont want to proceed with another clutch you can remove her to a seperate cage. She will lay off the perch. Maybe two eggs at most and then she will stop. It does not automatically mean eggbinding just because there is no nestbox.