This myth is not true. There is no automatic entitlement for you to continue living in a property until your youngest child reaches the age of 18.
If you have separated and are not married but you are a joint owner to a property and the other party wishes to sell the property and you do not, they can look to obtain an order for sale from the Court. Whilst the housing needs of any children of the family will be a relevant consideration in making any order, the Court is not obliged to order that you continue living in the property that you jointly own.
If you are separated and are married, the Court again will consider the housing needs of all parties, and particularly any children of the family, however may make an order that the family home is to be sold prior to the youngest child reaching the age of 18. The Court will consider all factors when deciding the best way to divide the assets of the marriage to best meet the needs of the parties. Of course, in some scenarios, it is the fairest outcome for one party to remain living in the family home, however it must be understood that this is not always the case.
It is important that parties do not avoid dealing with matters as a result of the false security that they can simply continue living in the property as they have young children. It is advisable to get advice as soon as possible following a separation.