I’ll start.
2 siblings, all very close in age
Growing up we didn’t play together loads and certainly from age 8/9 onwards we just played with our own school friends and I didn't interact with my siblings much.
(This was party probably influenced by the fact my parents didn’t do stuff to help us bond, e.g. we didn’t really go on family holidays or have shared hobbies or interests)
Money was quite tight with three kids in the house so I didn’t get to do stuff I would have liked e.g. I was desperate to do ice-skating as a child but my parents couldn’t afford it / manage the logistics so I didn’t get to do it.
As an adult my sister has mental health issues and is hugely reliant on my mum, meaning I never get to spend any time with my mum without my sister (they live together and mum refuses to leave sister home alone to come and visit me, I now live the other side of the country so it’s an overnight trip). So it’s massively impacted my relationship with my mum & not in a good way.
My younger brother moved far away and does his own thing / isn’t very communicative so I don’t have much to do with him at all, although he’s pleasant enough.
So overall although my siblings are good people, I don’t understand at all when people say a child needs siblings.