Whole bed frame moves when Sims want to sleep (Solved)

What was the process you used to make this bed frame?

I still think you would be better off making an entirely separate frame that has no mattress at all. It's a path that's much less likely to end in problems and it has the added benefit of allowing people to use your frame with other bedding colors. That said, if you post this item I can take a look at it.

This is happening because somehow you assigned the bed frame to the wrong joint. The bed frame should be inert in the game and all inert parts of the mesh are assigned to the Transform bone. Instead the frame is assigned to one of the blanket joints so it's moving whenever the blanket moves.

To see that yours is not assigned correctly:

1. go into Edit mode
2. change to smooth shading
3. click n on your keyboard to bring up the side bar menu and then put a check in the Show Weights box. Click the small inverted triangle to bring up the joint list and select the transform bone. The bed frame will be blue indicating it is not assigned to this joint:



If you then click on the first joint in the list the entire frame turns red indicating it is 100% assigned to this joint.  To fix this select all the vertices of your bed frame and click the Remove button.  You can turn of the weight coloring to make selecting the vertices easier if you want to.



Once that's done you will see the frame turn blue if you turn Show Weights back on.  After that click the transform bone line again and click the Assign button.  You will see the entire bed frame turn red indicating it is 100% assigned to the transform bone.  



Save the .blend and import that back to your .package.  Repeat this for your LOD 1.  Test in the game.  The bed frame, now assigned to the correct joint, won't move with the covers