To cut ties with my mother?

[Tashajay8]

My sister who is in her early 20s lives with my mum. She was pregnant and had a baby at the beginning of the year and had the baby adopted. I have just found out and am devestated. My sister was understandably scared as this was not a wanted pregnancy. However I saw my mum every 2-3 weeks during this time and she never mentioned it. Furthermore she purposefully kept my sister from seeing me over Christmas as she didn't want me to know and she doesn't want her to tell anyone else in the family. I have met with my sister today who had said she may of kept the baby had she had the financial support (which my mum apparently couldn't give her). I am not really close to my sister or my mum but Part of me is thinking this is unforgivable and am wondering if I should cut ties with my mum. The only thing holding me back is the fact I have a daughter myself and don't want her to blame me for her not seeing her grandmother when she's older. However my mum has been in a controlling relationship for the past 18years and only sees my daughter for 2 hours on a specific day once a month as that's the only time that fits in with her controlling partner. So she's not exactly an involved grandparent. Just wondering what other people would do in this situation?

If your sister wanted you to know about the pregnancy why didn't she just tell you herself? I'm not clear on why this lack of communication is your mothers fault.

I didn't see my sister during the whole time she was pregnant as my mum was keeping her away (she doesn't drive) and telling her not to tell anyone as it would cause a drama. And my sister is easily controlled by my mum and basically does whatever she's told.

I'm not in your shoes, obviously, but it should have been more your sisters decision to share about it, not your mums. And it sounds like it would have been a drama. What would you have done if you had known?

are you upset because you feel you could have supported your sister had you known and maybe she would have kept the baby? Are you upset because you think your mum basically bullied her into having the baby adopted and did it by cutting her off from everyone who may have helped her?
Because if so I can see why you are angry...

If it was partially your sisters wished that you were not told then you dont really have any reason to be angry with your mum.
Your post is a bit unclear about the feelings of your sister

I would of supported her anyway I could of if she wanted to keep the baby or even if the result had been the same. I am upset that she didn't get that support as no one knew except my mum, who would of wanted her to have the baby adopted (even if that was my sisters decision) so it didn't impact her relationship or affect her life as they live together. She didn't even tell her partner who lives there until he accidentally found out.

Sounds like a very complicated situation OP, my heart breaks for your DSis and her little baby :( I just wonder though, if you go NC with your mum does that mean you will effectively be going NC with your sister too since she doesn't drive? If so, I wouldn't do it as your sister may very well need your support in the coming months, years if she has regrets about giving up her poor baby.

I might be wrong but I believe that your sister can reverse her decision up to a year or so if she changes her mind, if you feel she may have made the decision for the wrong reasons you could talk to her about it, take her out for the day away from your mum?
I wouldn't cut ties with my mum I'd try to strengthen the bond with my sister. Its understandable that you're angry & upset but its not the time to make decisions that will upset the family more. Your sister has been through a huge trauma. I think its sad that your mum didn't help your sister by helping her access different opinions & support from you & the rest of the family. She seems to have dealt with the pregnancy like its something to hide which might give your sister the message that she should feel guilt & shame.
Have you asked your mum why she didn't tell you? I would tell her how you feel about being kept in the dark, I mean in a situation like that the whole family should have the option to help support each other.