Hello and thanks for your question.
If a couple decide to divorce, then once a divorce petition has been filed at court, either party can ask the court to decide how the matrimonial assets should be divided between them, if the couple cannot agree between themselves. The matrimonial assets arae everything in each person's sole name, plus everything they own jointly. The court starts from the position that the assets should be divided 50:50 - then looks at reasons why that should not be so. For example, if there are dependent children then the person who provides a home for them can argue for more than 50% of the assets. Or if one person has a significantly lower income than the other, they can argue for a greater than 50% share.
Even if your sister earned more in the past, if her income is much lower than her husband's now, she can argue for a greater than 50% share. If her husband is yoinger than her, and still has many years to contribute to a pension scheme, or even just has the opportunuity to increase his income in years to come, while her income remains static, these would also be arguments for a greater than 50% share.
If her financial needs are greater eg if she has a disability or had to retuire earky ion health grounds, then again she can argue for a greater than 50% share.
However, her husband WILL be entitled to a substantial share, even if not 50%, it's unlikely to be less than say 35% or 40%.
Your sister needs to see a specialist family law solicitor to discuss her situation in details. Here's where to find one:
As going to court is stressful, time-consuming and expensive, if your sister can negotiate a settlement either between herself and her husband, or via solicitors' correspondence, or via mediation, that would be preferable. The family court nayway now requires the parties to have attempted mediatin before it will consider an application to court.Here's where to find a local family mediation service:
I hope this helps and I wish you the best of luck.
Thanks and best wishes...