Upset with my sister's behaviour... Advice please!

[PlumpPartridge]

My DSis is 7 years younger than me (mid twenties) and her behaviour is currently pissing me off. Our mum has recently been diagnosed with metastatic breast cancer and is in hospital undergoing treatment - this follows a long period after her mastectomy where we thought she was ok. DH, DC and I had to leave the family home after Christmas to return to work, so left DF and Dsis there together.

He doesn't live in the UK full time (it's my mum's home town) whilst DSis does. After we left I had expected forlornly hoped that she might make an effort to spend time at home with him rather than avoiding him in favour of spending days/nights away with her friends. She was only going to be there for an extra week compared to us anyway, so it didn't seem like a colossal ask. Surely any normal person would feel bad about spending two days away visiting friends when their dad was at home in some distress about their mum's medical condition?

Apparently not. There were other overnight stops away as well but DF hasn't gone into detail about them. I asked DF if she was at least planning to hang around the night before she returned to uni and he said he didn't want to ask her because he was afraid he wouldn't like the answer

I do love my DSis and know she struggles with family gatherings and talking to my dad as he can be a hypercritical idiot sometimes. I understand and sympathise with the impulse to escape, I do. I just am really fucking upset that she bring herself to make a special effort this time.

In the interests of not drip-feeding she has always obviously prefered her friends and their families to our home. This is piling more hurt on years of the stuff, not that she would acknowledge it if challenged.

Argh. I am itching to say something to her. Any advice?

I'm very sorry about your mother.

Your sister is dealing with this too. You know she struggles to deal with your father at the best of times. Please give her a break.

I would stay out of it, it is between your father and his daughter. Tbh if my dad was a hypercritical shit to me, I wouldn't want to spend time with him either.

My sister is 14 yrs younger than me and its like having a teenage daughter at times! Her attitude towards family and priorities have upset me many times... But. She must deal with this in her own way not your way. She is equally your parents daughter it is her relationship to maintain not yours. If you want to support your dad support him in your own way. I make a conscious effort not to involve myself in their relationship otherwise I wouldn't have a good relationship with my sister. Your dad can tell her himself what he expects.
Sorry your mum is poorly I wish her a speedy recovery x

Your father saying he was afraid to ask if your sister was going out as he 'wouldn't like the answer' makes him sound quite emotionally manipulative.

He is her father, and should be making an effort to support his children.

You at least have the benefit of distance and a family of your own to dilute the intensity of the situation you find yourselves in.

Your sister must find the whole thing very claustrophobic and uncomfortable, especially as she isn't particularly close to her father anyway.

I'd avoid criticizing your sister, and just do what you can yourself.

Sigh. Alright, I won't say anything. It's just so disappointing and also hurtful.

Am I allowed to elaborate on the situation without being accused of drip-feeding?!

When we all lived together (in another country) my mother was definitely the most difficult person in the house to live with and we all survived how we could. My DF clearly prefered me, which was/is unreasonable of him and I have tried to get him to see that DSis is desperate for his love and attention too. On the other hand, our mother clearly disliked me and thought/thinks the sun shines out of DSis's arse. The situation has improved with time and distance (I more or less try to get on with my mother now that she's not such a bitch anymore, DSis makes a conscious effort to chat to DF about things he might be interested in and he tries to chat back in a way she's happy with - i.e. not stating any fixed opinions and accepting that different views are possible as she gets very agitated about fixed views that don't match her own).

That's why I am disapppointed, tbh. I thought that things had improved to the extent that she would feel sorry for DF and want to hang about and try to cheer him up about the situation. I think that in a parallel situation (i.e. DF in hospital and DM at home fretting) I would make an effort to keep her company and provide support, even though she did treat me like shit for the majority of my formative years. I feel like I would go down in my own estimation if I didn't at least try to be there for her in such a situation. That's why I am angry with DSis and judging her behaviour on this score.

Admittedly my confessed preference for my dad over my mum (and DSis's vice versa) has probably coloured my judgement on this, but I am trying hard to maintain some measure of objectivity. Even DH, who normally forgives DSis all her misdemeanors as I perceive them and tells me I'm being harsh, says that he's not sure her behaviour was very good here and that he expected different.

This is part of why I'm consulting the Mumsnet Massive; I am not entirely sure I am being fair to her.