5 years between me and my big bro and we get on great, used to fight like cat and dog as kids but loved eachother dearly too LOL x
My son is 9 from a prev relationship, and we have a 13 month old girl and another on the way in December. My son is the best big bro ever, he is a fantastic little helper and my daughter absolutely loves him, and they have a great bond already, it is so clear to see, My son is just so protective of his sister and loves being with her, and she gets on his nerves sometimes too LOL because that's just kids.
My partner just puts it down to how they are brought up and how much we involve the kids with each other and with us, yet make time for both individually so they get time on their own with us or just mum or dad time.... because we r a family but we are all individuals too with different interests and needs x
no matter what the age, or the little fall outs along the way, they will be brought up to know that family are the ones they can turn to no matter what and to be there for each other and look after each other and to be respectful of each other x
we both work, me part-time and my partner full time, I'll be on mat leave soon though x we just make it work x and love each other dearly, it has its ups and downs but rules and discipline and some kind of routine helps x