Posting for the first time in a while, feel like I shouldn’t be here (I live in nz now).
We had a 3rd, planned, but I don’t think it really makes a difference.
Personally I found my 3rd a whole lot easier than the previous 2. When she arrived I had one in reception and one in nursery (there’s 5 years between #1 and #3, 16 months between #1 and #2). It felt like she was an only child in a way, we had the days to ourselves while her siblings were at school.
Definitely echo what was said above. Space, both in cars and in homes, becomes an issue. Third children just have to fit in, from day 1. I’ll never forget doing the school run on a cold January morning with an 11 hour old baby (hubby had gone to Heathrow to pick up my Mum). That was just the start of her life as a baby sitting in the wings of ballet, school, football, music lessons etc.
My baby is 7 now. She’s infinitely more pleasant than mr 12 and miss 10 (going on 16). Sometimes it’s nice to have 3 to choose from
It changed our family dynamic for the better - My two youngest play well together (both girls), as do the two oldest. Wouldn’t change it, but would never have considered having any more!