What is interesting, only the first cat was with me since her birth, and was not fixed. Second one was abandoned, fixed in shelter, and was about 1 year old when we met; cats I share house with now, are both fixed, and were 4 and 3 yrs old when joined our family.
Not a big sample, but it makes me think that first months of any creature's life determine their preferences and phobia a lot. Not sure about influence of reproductive functions though



