Ketu in 4th house represents the relationship of the native with his mother, and since Ketu is an evil planet, there is no more general oversight for mothers. If Ketu is on the bad side of the fourth house, the mother may not be interested in the native as a child or as seen, and she could abandon or try to get separated from the native, and hence the native tends to have less nourishment from the mother.
Ketu is often associated with mystery, secular detachment, liberation, artistic wonder, etc. Ideally, Ketu is the creator of psychopaths, criminals and serial killers; however, it can also help create famous, dignified personalities like magicians and investigators. Ketu is a dark planet and doesn’t work great in the fourth house, and it might create events of personal harm to the native emotionally, physically or financially.
Ketu in the 4th House in Astrology is in a neutral position. It gives average family life, but it doesn’t damage the house since Moon rules it.
Ketu in the fourth house is representative of distant travels, foreign lands, and therefore it might lead to migration to overseas territories. It signifies the loss of property and can make the native aggressive towards others. As mentioned earlier, it negatively affects the motherly nourishment and can also affect the relationship between the native and the mother in the early stages of childhood.
There is emptiness about the natives' happiness in their homes, leading the natives to face problems with family and friends. However, Ketu in the fourth house can also lead to the inheritance of property or wealth from the mother.
The native with Ketu in the fourth house begins donation in charitable organisations and social activities and will be financially stable, and this will entice others to take recommendations from the native.
The 4th House in Astrology represents home, family life, ownership of the home and vehicles, peace of mind, childhood, teachings of the mother, grade school, and any kind of conveniences. Having an air conditioner is also considered a 4th house object since it represents convenience.
The 4th House represents full awareness of having a home and mother, which gives the most significant experience. The home environment and extensive interaction with the mother cultivates a frame of mind and emotions. The mind and emotions are, in turn, the basis for happiness.
Physically, next in line, after shoulder and arms, is the chest, including the heart and lungs. The signification of the heart reinforces the significance of emotions.
The correspondence with Karka (Cancer) adds a connection with water and water bodies and again reinforces the signification of mind and heart.
Ketu is the south node of the Moon and the rest of the body of Rahu. This is a headless body representing separation, isolation, and the abandonment of the material world. This shadow planet represents spirituality, nothingness, and goals that were already achieved in past lives. In this life, we only rely on those things as a last resort.
Ketu in Astrology is also an unsteady and treacherous force, but its qualities are more of an abstract,inward nature than Rahu, who is more concerned with outward, worldly matters. Ketu can bring hindrance and obstacles in the physical realm of life but indicates sparks of intelligence and the mind's brilliance.
Note: The degree of auspiciousness and inauspiciousness will depend upon a complete analysis of the horoscope (birth-chart).