Connected Bone Parenting Issue with IK Constraint I have created a model with movable eyes. This uses two separate UV Spheres which are parented to their bones. These bones are then set to an IK bone in front of them. My issue is when I connect the eye bones to the model's armature, the model tips forward when in object mode. In edit mode there is no issue.

Here is a screen shot of the eye bones not connected to the armature in object mode:



Here is a screen shot of the eye bones connected to the armature in object mode:



I can upload the actual .blend file if needed.
Have you setup the IK constraint's Chain Length setting? Its default value of 0 means the whole chain of bones, right up to its root which is the head, will be affected by the constraint. You'd need to limit it to whatever length of bones really need the IK behavior, in this case 1.



If you want to make eye target controller, IMHO a Damped Track constraint would be more appropriate than IK, because it works on a single bone and very easy to setup correctly. 

Each eye's bone need not be connected to the head, BTW.