Agreement with Leed on staying out of it.

Regaining your relationship with your ex aside, I think it's the best approach especially with a child involved. With the complicated lifestyle that your ex is living, your child really should have someone there that has a solid footing without being mixed up in the mess that's surely to be coming down the road. be the sound voice for your child by remaining uninvolved. Even if you have feelings about the situation, keep the space between you and the situatioin for your kid. he/she needs stability and getting involved in it will undermine your being able to be the rock they can lean on

Hope this helps.
~s4