If you have a family member who is a British citizen or otherwise settled in the UK, you can apply to come for up to six months as a family visitor.
The main requirements are that you must provide details of your family member, show your travel plans, and prove that you have the money to pay for your journey, as well as show that you intend to leave the UK at the end of your trip.
This visa does not allow you to work, live in the UK for a long time, get married, study or receive private medical treatment.