It depends on a number of things, such as if one of you is moving into the other's property, or if you're buying somewhere together. You will want to think about documenting contributions to property assets, provision for the survivor on death and how to structure them being able to continue living in your home and, particularly, care for the children you have together.
Yes. Cohabitants do not automatically inherit assets on death like spouses or civil partners, unless those assets are held as joint tenants and they pass automatically to the survivor. It's therefore important to review your Wills before cohabiting with someone.
Yes. Marriage (or a civil partnership) revokes a Will, although Wills can be made in expectation of the marriage or civil partnership. Both change the Inheritance Tax treatment of your estate on death, so advice should be taken.
You may also want to consider a pre-nuptial and post-nuptial agreement if you want to protect the assets brought to the marriage. We can put you in touch with a family lawyer at gunnercooke who can assist.
The Lawyer in London