Half sisters when one sees dad, and the other doesn't.

[ThisMustBeMyDream]

Sorry for the long winded title. I couldn't think what to put!
I'm looking for advice or just a friendly ear to mull over a particular thing SD has told us tonight. SD is almost 5 and has an almost 8 year old half sister . She doesn't see her dad. SD obviously does. SD told us that her sister teases her by telling her they have lots of fun and do really cool stuff when she isn't there, and she gets upset when she does this. She was quite clear in her opinion that her sister was being mean rather than just sharing what she has been doing. Clearly she is jealous of SD having her dad in her life, understandably. DP wasn't with her mum for more than a couple of months, but he has always tried to consider her sister when doing things for SD. Eg during lockdown mum refused contact for a long time, but when she did agree to it, it was in her garden when he was only allowed to sit there and watch. Obviously both children would be there so he would take things for SD like a little toy, magazine or sweets or things to try and interact but whilst not having physical contact, but would also take the same for her sister. He did the same during video calls when she stopped him having midweeks during the 2nd lockdown. He read stories to both children. When my son had an online birthday party, and SD was asked to join from mums, her sister was included in that too. There are other examples, but I'd be here all day listing things! What I'm saying is, he is mindful of this situation and in not adding fuel to any fire.

When SD told us this, DP told SD that she gets to do cool and fun stuff when she is with us, so she isn't missing out. In retrospect I wonder if maybe he misjudged how to approach it. I'm not sure what he should have said or done though. His daughter is upset, and her sister is obviously jealous and also upset if she is saying this to tease her little sister. Mum is difficult to handle, so the obvious thing of speaking to her so she can address it with the children in a sensitive manner simply won't work. It will just cause big issues.
Does anyone have any snippets of wisdom that I can share with DP, particularly if it is a situation you have found yourself in with your step or or biological children.
Thank you!

Sorry if it isn't immediately clear the half sister is in relation to them having the same mum, but different dads.

I’m not sure what the mum or Dad can do in this situation? It’s very unfortunate that the eldest doesn’t have that relationship with her own Dad. I presume your partner doesn’t want to have both children if there is not really any relationship with the eldest? I would just reassure the younger one that her sister is winding her up because she’s probably a bit jealous and wants to make herself feel better. Many siblings spend a lot of time winding each other up for various reasons, I wouldn’t get too worried about it

I’m not really sure I see the problem? The mums doing fun stuff when the daughter is away so the other child doesn’t feel upset? Can’t get worked up about that and I don’t see the problem? Not the same but my son use to go to sports club and didn’t like that me and the other kids were at home doing stuff without him, he seemed to have built it up in his head that we was doing all this fun stuff without him, no one told he we were he just came to that conclusion so it’s perfectly possible the 5 year old is as well.

Not really for dad to get involved other than reassure his child. They'll have a difficult dynamic growing up but mum can't put her other child's life on hold everytime one of them is elsewhere.

Dp offered to have both when SD was a baby and was assaulted for it (head slammed repeatedly with the door, and hit with shoes). As I say, mum is incredibly difficult. She doesn't want SD to have contact with her father. So, no, it would never happen. Unfortunately.

No one is saying mum shouldn't do anything when she isn't there (we don't think she is anyway, but that's not the point). The question is how can my DP help his daughter manage any emotions she might have given he can not talk to mum about it. He wants to protect the relationship as they are getting older and jealousy comes in to play.

I'm confused do the have the same df your dp and different mums or different dads

So in that case whats it to with ops dp? Kids argue not his place to get involved.

I think he did the right thing. Reassure her. There's nothing more he can do.

You partner should handle it in the way that he is doing. There will always be children who have more or do different things. I would not necessarily assume that the other child is jealous. She may not understand why your partner's behavior has changed towards her. The mom is obviously trying to compensate and has probably not bothered to explain to the daughter that she cut off the contact.

I would not look at this as anyone being in the right or wrong but just as an opportunity to help daughter understand that there will be many times that people have and say things about experiences and objects that she may not have. If she is old enough to articulate complaints, she is old enough to begin to understand that she will have and do things that others do not have or do and to understand the reverse as well.

How is "noone in the right or wrong" when the mum assaulted DP?

Why minimise that?

and was assaulted for it (head slammed repeatedly with the door, and hit with shoes).

Did your dp report the assault ?