When the ruler of the fourth house is in the third house, this means that your siblings may be traditional, displaying the beliefs of their country and parents, and attached to parents and the home/country of their birth.
The siblings can be landowners or may own their own home. They may be involved in real estate or some sort of land business, or may work with the natural resources of the earth. They may be stable, reliable, stubborn, practical, and realistic people.
The lands or properties they own may later become yours. You may be close with your siblings and you may be similar in character or beliefs to them.
This placement also means that there can be many changes in your living situation, such as you having to move homes more often than you plan. There will be many other major changes in your life, more so than for most other people.
This astrological placement also means that you are an adaptable person, quickly adjusting to major life changes, such as if you need to move to live in a new place.
The ruler of the fourth house in the third house may show that your parents also had a life full of changes, and this placement can indicate that their occupations are interesting and always giving them new experiences.
This placement can also show that your parents are communicative, lifelong learners, curious and interesting people.
Such a placement may show the natives living in movable homes; like homes on wheels, or if their homes are their cars.
Your home may undergo many changes throughout your life there, such as being decorated and redecorated, for example.
You will experience so much change in your life that this will become normal to you, and you will actually derive a sense of stability from constant change; and you won’t feel yourself if there’s some stagnation in your life.
You may take regular trips in your own country or the countries nearby.