I wrote another post talking a little about my situation with my husband, his son, and his ex-wife.

My husband has had primary physical custody of his 12 year old son since he was a few months old. He has never asked for child support from the ex. The ex has been in and out of her son's life, she has never been stable as far as work, relationships (divorced 5 times, she is 36), or living situation. She has another son who is a couple years older than my husband's son, but she gave her mother custody for that child right after he was born.

The ex occasionally takes us to court to try and get primary custody (usually for off-the-wall reasons), but has always been denied and has been called an 'unfit parent' by judge. So husband's son (I call him my son, too) lives with us, and occasionally goes for a weekend to see his bio mom.

My question is kind of a two part question... if something happens to my husband, would I probably get custody of his son - since "mom" is detremintal to his well-being and has never had custody... and if it is questionable, at the age of 12, could the child have a say on who has custody? I have teachers, his counselor, his doctor, husband and my own family members to vouche for me, not many, if any for her...

A step parent adoption would solve this issue. Your difficulty would be getting her to sign off, or getting the court to declare abandonment, it would depend on the length of time she goes without seeing/calling/inquiring about him. Talk to a family lawyer or your friend of the court office for some help.