Mother in law showing favouritism to her daughter over her son

[Bobbitypop]

My mother in law seems to have double standards when it comes to her daughter and her family and her son (my husband) and our family.
Both her son and daughter have struggled with their mental health in recent years and while she’ll be empathetic to her daughter and excuse any bad behaviour due to her mental health the same is not done for her son.
she regularly has got us/asked us to help/support her but never seems to be the other way around? If we go over then she’s always there with her kids and we have to help look after them along with our own two young children. When my husband asked for help with our kids during a weekend I’m away she said he had to drive to her and called him a chicken when he didn’t want to drive there and back by himself with two small children (3hr drive in total) yet has recently told us to make a journey to his sister because she can’t drive with two small kids but yet he can?
She regularly tries to talk to us and criticise us about parts of our parenting she doesn’t agree with but will never speak negatively about her daughters choices.
she regularly spends time with her daughter and looks after her children but it’s not the same for us.
when we have invited his parents round they bring their daughter and her children (without even asking if it’s okay with us).
my husband has tried talking to her about it but she gets defensive and also insisted her daughter be there when he just wanted to speak to his mum only. I believe she did apologise in the end for making him feel that way but yet nothing changed.
Its really affecting our relationship with his family and my husband is finding it quite upsetting. Not really sure what to do.

My mil shows very obvious favouritism and has a strange dynamic with DH compared to sil. Sil walks all over her, but in a “nice” manipulative way. Mil thinks everything SIL says is the best thing since sliced bread. Mil has no qualms in offering unsolicited advice to dh regarding everything from children to our house, yet wouldn’t dream of trying to advise sil on anything. Sil lives & works in London (highly skilled professional, no kids, extremely high earner) yet despite such a huge income, she won’t put her hand in her pocket to even pick up the tip for the waiting staff when we’re out having a family meal. It’s a running joke in the family that she’ll get her dad to buy her round of drinks at the family Christmas get together, except it’s actually not funny.

Sil will book all of the new/expensive restaurants she wants to try when she comes home to visit, and in-laws will drive her there, whatever the distance, and pay the bill. Dh & I have 3 children (the only grandchildren) and they wouldn’t take our kids, even on an individual basis, to the local soft play centre on a rainy day- as god forbid it would cost them a fiver.

Mil would probably fall over before thinking of offering to babysit for us to actually get out & have even a few hours downtime as a couple, yet she thinks nothing of landing round late on a school night when we’re busy with homework/bedtimes etc, and will stay way beyond the kids bedtime, then shoots off at 8:20- because she has to get home in time for a tv show coming on at 8:30. Both her and sil are quite thoughtless and selfish, tbh.
It’s quite hard to watch on as the other important women in his life treat him rather poorly. His father is more equal in terms of treatment, but he generally just does whatever mil says or suggests unfortunately.

I know the situation is not the same as yours, but I understand your frustration with the relationship. I think mil & son relationships are very complex, mothers seem to have a strong hold over them somewhat. I know my dh is very poor at setting appropriate boundaries around his family, or being upfront with them. It has massively affected our relationship over the years (obviously over more serious issues than the small thing listed here)

Not quite sure how to advise you OP, sorry. But you are not alone 😏