To not “babysit” my stepchild?

Difficult.

On the one hand, you married a man with a young child, so you should be “all in” and expect some parenting responsibilities. On the other hand, your DH seems to be totally taking the piss with the amount of time you are looking after the child for, with very little gratitude.

That said, there are several cliches that come through your posts. The mum has MH issues, she is in and out, she needs wellbeing time, she can’t have the child for xyz reason. It paint her as a “mental ex” without saying that explicitly. Why would your DH have a child with someone unstable? Why was he married to her (presumably)? It seems there might be more to it. More that you can’t see or are choosing not to. Like your DH being a total cunt. He’s looking like divorced father of the year for doing such a lot of parenting, but you’re the one doing it, along with granny.

Perhaps he treated his ex in this way - nanny with a fanny as someone says above. Perhaps she’s broken from it.

Poor little kid though - from pillar to post all the time - school, mum, granny, daddy, step mother who has had enough. His MH could turn out to be shitty.

I would think very carefully about whether you want to remain in this marriage and potentially bring more kids into this mess. Things are not likely to get better. Only worse. And your DH clearly is one of those men who will palm his kid off on any woman he can get to do it.

Your DH thinks he hasn't just gained a wife, he's also into the bargain got a live-in nanny.

You both rushed into this marriage without really discussing what ifs.
I think your Dh is wrong to expect you to do it. He should be adjusting his work to parent his child. Both parents see you as a walkover.

And yet…. Neither the mother or the father is available at weekends.

Why should @namechangedcusillbeflamed be the defacto parent when the bio parents aren’t doing their share?!

@namechangedcusillbeflamed you are a team now . However he is totally taking you for granted .
Id be calling him out . Asking did he only marry you for childcare ?
The child has a mum , dad and grandma .
I am sure they can mange .
I would help out on school days doing bath and bed but he needs to not do extra shifts on his weekends as he doesn’t have childcare . Simple

If his Mum needs her weekends for her wellbeing, you should be allowed them too. YANBU. You clearly do an appropriate amount for a step mum and I imagine would be happy to help in an emergency, but making it your job without really discussing it with you is not on. You need to have a frank conversation now with your husband before it becomes a real problem. He needs to stop working on weekends if he has his son or rearrange the schedule.

He has picked up the extra shifts because he now has you, which tells you exactly how he views you as his wife and shows you what he will be like as a father if you have children together.

In your position I'd double up on contraception.

Exactly this. He is there to have time with his dad not you. If Dad works Saturday and then late on Monday and Tuesday where is his quality time? Poor lad may as well just come on Sundays as not sure when he sees his dad in this arrangement especially with typical young child bedtimes. Your job is to support your partner and to try to be a positive and supportive adult in stepson’s life but primary caregiver in your house should be his own parent.

Did you honestly think that throughout a child’s entire life that nothing was going to change? Children grow, their needs change, the health of their parents changes. It was ridiculously naive to assume you’d never have to do anything outside of the set 50/50 hours.

Every weekend does seem a lot, but if it’s genuinely what the child’s mother needs in order to stay mentally healthy enough that her child doesn’t have to live with his father full time, then so be it. You are free to make other plans on the days your DH wants to work overtime.

Also, I hope you’ve had CMS adjusted if you’re now having the DC extra nights regularly.

I'm a SAHM to my own biological children op and my husband ( their bio father ) calls to check with me first before staying on at work longer and half the time I say no thank you, he doesn't complain either.
Your husband has engineered this, he has no respect for you.

Both parents have palmed the poor child off on you. Not acceptable. He needs to be with his parents. Both need to step up at the weekend. Youre not some kind of unpaid nanny with a Fanny. He didn't even ask. The cheek of it.

What happens to DHs overtime money that he gets for working weekends? Does it go into the family pot or does he keep it for his hobbies or to give to she-who-has-mental-health-needs?

I’d be expecting you to benefit from it 50/50 since youre the one facilitating.
If he needs to work extra to pay for children’s clothes or give money to her I’d be telling him to tell her that if she wants money/things from him then she needs to look after dc at some point over the weekend to allow him to work as his wife (you) has things to do and cant do childcare every time.

Your DH is completely out of order. To be honest, i dont understand why any parent doesnt prioritise being there for their kids. But his son has been through a lot in his short life. Separation and his mum's problems. Now his Dad doesn't look after him in the evenings or for a big bulk of the weekend. How can you stay with a man who doesn't put being with his son first?

If you are going to stay in this marriage I think you need to be committed to being the boy's parent. See him as your son, and love him. He's not an errand getting in the way of your real life, being his parent becomes a rewarding and meaningful part of your life. Not saying that's easy or will come naturally but it is reachable, if it is a life you want. And that's a big if.

The boy deserves one parent who loves him and wants him. If you and DH can get on the same page maybe he can have two parents who love him

i get where you are coming from but once you are married and live together you are official the step mother and I would argue there are responsibilities that come with that as you are expected to slip into a ‘mother’ type role. It isn’t the full role, obviously, but I’d expect that you would look after them child if your husband isn’t there with all the relevant tasks associated until the father gets back. You are the de facto parent in that time.

if you weren’t up for it, I’m not sure you should have got involved with them as they come as a team.

Id say the issue is that your DH changed the set up without any discussion with you. That's not on.
Its reasonable to expect you pitch in to the household, but not for you to be doing the lionshare of childcare. If he expects you to pick up the parental responsibilities are you extended the same rights? The same inputs into how the boy is raised?
Id be really unimpressed tbh, he's outsourcing his own responsibility to that boy.

if she doesn't want to be around the kid why did she marry the dad really the mum sounds like she has mental health difficulties that not something you just decide on a whim she either needs to grow up and accept things or walk away

Did he ask you before doing extra shifts or just assume you'd have his kid?

One week on one week off would be better, when do you ever get a weekend to yourself?

But what kind of a father starts taking on more shifts on the exact days he has his son? He didn’t have those shifts before so why now? Without discussion with his wife. If they are all now a family, surely they need to discuss this first…as a family.

It’s a lot for you and definitely should have been discussed before you got married. You should be there to support his parenting, not be the lone act. You need to speak to him.

I would inform DH I have plans for the next few weekends and see what he says. Remind him this is his child and he needs to spend the time with him

dh has changed the goalposts since you got married, that’s not on. You need to tell him that his contact time is to see his son and he hasn’t seen him much oh be out for the next few weekends to facilitate this.

If he sent ds him to his grandmother to care for then you have your answer.. he doesn’t want to parent, it’s easier to go to work , which is true of course you only need to think of yourself and not about feeding and entertaining a child!

I hope you are at least benefiting from the extra income op!

Play the tape forward and accept that DSS is going to be around every weekend. Tell DH you don’t need or want the extra household income. It sounds as though DSS could end up living with you full-time.

Wow. Well, you know where this is heading.

This would be make of break for me, I'm afraid. Good thing you haven't been married long yet.

Do you want children of your own?

He's shown you what kind of father he is, palming his kid off on the nearest female whenever possible. I hope you have good contraception.

He’s not her son, and that he’s a family member does not make her responsible for providing childcare.