Hi, thank you for your question. Just a bit more information required to fully assist you:
-Are you married to each other?
-Is the title in joint names?
-Are there any court orders excluding you from the property?
Thanks for confirming. Legally she is not allowed to change the locks without a court order. He has a legal interest which entitles him to occupy the property and also obtain a share of the proceeds of sale (or for him to be bought out for his share). However, as they are married and have two children the main carer of the children will likely have the higher needs and therefore be able to persuade a court that the property is required to accomodate the children - but in respect of your specific question legally he will be allowed to return to the property unless a court order is in place excluding him.
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