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Thanks Pizza and Joe. I had a lovely birthday evening in the end and I did manage to speak to my sister, who was very understanding about how my time was so restricted this week. I don't resent the time I spend with her or the children at ALL, what DOES bother me is when more and more is asked of me, as though I'm a third parent.
We should all have a choice as to how much time one wants to spend with anyone, be it a friend, a work colleague, a family member. Everyone I know thinks I spend a huge amount of time with them, which suggests to me that it's far more than other people with THEIR families!
When more is expected of you than you want to give, it becomes an obligation, not a pleasure. I'm very happy and very lucky to have a niece and nephew living nearby and I know in years to come I'll treasure the memories. For me, though, this is an issue between my sister and me. It's an on-going battle but your help has been magnificent - thank you so much for your support.