Take care of yours.  Don't feel guilty about it either.  You are right that SS has another parent to look out for him (whether she does or doesn't, that's on her) not your job to make up for it.  

Are you the beneficiary on any of your DH's policies? It seems odd that your policy goes to him and his policy goes to his kid and another policy you both have also goes to his child. His primary policy should go to you, with both kids as alternates. Your primary policy should go to him with just your child as the alternate. Then the third policy can be split between the kids.

You should really get a proper will or trust in place.  There would be issues with a minor receiving an inheritance.

But yes you should change it to your bio only.  I would not make DH a beneficiary unless it's mutual.

As other's have said you need to make your child the beneficiary. If he doesn't change his policy to benefit your child together that would be a major issue. If he doesn't, your child should be sole.

I think you are very generous thinking of your SS in regards to your own life insurance policy. It is not an easy conversation to have. My DH did 25% to SD and 75% to me until we married. He changed it to 100% to me for our kids because SD has another family if anything happens. He didn't want to be thought of as a monster either but no one questioned it. Take care of your own first.

Did I understand correctly that SS is the primary beneficiary on your husband's policy? If that's the case, I would change the beneficiary on yours to your child, once he arrives (actually, to a trust for the benefit of your son).  At a minimum your child should be the secondary beneficiary.  You don't need to include SS; his parents should be taking care of him. 

How would you even think that this makes you sound terrible? If your husband dies, his goes solely to SS? Will he update it once the baby is born to include him/her? Are you provided for in any way if your husband dies? I would consult a lawyer to make sure everyone is taken care of. Also, does SS have a mother? If so, is she able to care for SS? Does she work? If so, there's a good chance she also has life insurance. My job has it and i have my kids split as equal beneficiaries. To me, a parent should do this to ensure their kids are cared for equally. Unless BM is dead/in jail/unfit, and SS has no other family, you won't have any rights or control at all over SS. Just something to keep in mind. And BM won't have any rights or control over your child if something happens to you. Kids are provided for and cared for by their legal guardians. In your baby's case, that's you and your DH. In SS's case, that's your DH and BM. Not you. 

Absolutely look after your own, first and foremost. 

And I agee with the other comments. It's totally weird that you are not the beneficiary on his own life insurance policy. That's just not right.

You should be the beneficiary. He should be yours. And you both should discuss your wishes in case of death, and god willing you trust eachother enough to carry them out.

This actually makes me wonder how people plan their will / estate when stepkids are involved.  It makes me cringe thinking about SD getting the lions share from BMs side where there are no other children but multiple sets of grandparents, wealthy aunts, etc, and then on top of that getting half of whatever we leave for our daughter.  Makes it hard for my husband to make sure his kids are treated fairly when we are gone...on the flip side I suppose SD could also be left with piles of debt...

What have you folks done?

Both my kids are listed at like 35% each and hubby 30%. No skids come under it.

the way i see it, the only people i consider eligible for a portion of my life insurance policy are people who add to my quality of life, not those who severely contribute to a deterioration in my quality of life (aka skids).

my husband has a work provided life insurance policy and i am listed as beneficiary of it. The way hubby figures it, we have 2 kids aged 4 & 5, skids are currently sd(almost 26), ss23.5 and sd(almost 17), if hubby were to die all skids would be grown up and if youngest sd is say 18 or 20, she's opd enough to get a job and support herself as the other skids. 

me on the other hand have 2 minors and if hubby has provided for his kids from exwife their whole lives, he needs to do the same for me. Since exwife has lived off cs in order to never get a job and marry just to never have to work a day in her life, it's hypocritical for my husband to feed me to the wolves and expect i fend for myself with 2 littles whilst he's handed a silver platter to his 3 failure to launch kids.

i'm also in the process of handling my late mothers estate and will ensure skids never see a dime of it. Any holiday trips we may go with that money, is me, hubby and our 2 young kids. Skids can suck on it and as my husband says, skids have one another to help out.