Putting this in Chat as it's all hypothetical.
SIL has got married. It's a 2nd marriage for both of them. Both are English and lived in England. They have now moved to Scotland. SIL has sold her English property and used proceeds to buy their Scots house which is in her name. Her husband is keeping his English house and renting it out to provide an income for both of them.
If they were to divorce in Scotland, how would the property be split?
Any Scots lawyers about?