Coming from the opposite end of things, I've had really positive experiences with large age gaps and seen not so great ones with small gaps. My sister and I are seven years apart and have always been close. Similarly, my husband and the sister he's closest to are nine years apart, whereas he is not at all close to his other sister who is two years younger than him.

I think avoiding competitiveness is one of the best things about 3+ year age gaps, as siblings I knew that had gaps below that always felt influenced by people's perception of the older one. It was more challenging for them to form their own identity and that often built resentment.

I'm still pregnant with my first, so I'm just a lurker on this sub I haven't posted in here before, but we are hoping to aim for a gap of 3 years to 5 years. The only reason we're leaning more on the three years is because of our ages.