My sister is ten years older than me and probably saw far too much of me when she was in her late teens than she wished she had to.

She didn't have a great deal of choice in the matter. While my parents worked, she was forced to babysit.

Later she was substitute parent, fulfilling her role when the ones ultimately responsible were otherwise detained. Retail hours are unforgiving. Newsagents can't easily take a day off. Wedding photographers have their Saturdays taken up. There was no choice. She had to deputise.

I remain unconvinced as to what extent this responsibility had a positive effect on our relationship. This may be a fundamental reason why we don't see each other quite as often as perhaps siblings should. We live only a few hours drive away from one another. And we rarely speak on the phone.

But there is hope. One day we will see each other as often as we did when I was a child. We'll catch up on what has passed, as though no time has passed at all.