In three weeks time, Mark’s wife, Hannah, will give give birth to a little boy. I have typed that sentence as I would type any other: as if it is not loaded with meaning. Not loaded with longing, delight and hurt.

Finley is utterly ambivalent about having a new brother. I think he can’t quite imagine what it will mean or where he will be in his Daddy’s pecking order. Hannah is utterly dreadful at involving him in what is set to be the biggest shift in his family life to date, and Mark is so very torn between the two of them.

So I sit by and watch from the side-lines helplessly. I mourn the children I will not now have and feel angry with Mark for not sticking in a relationship he now admits he should have remained utterly committed to. I want to throttle Hannah for turning Finns room in her house into the babies room, without so much as a bed for Finn to sleep on, and instead insisting that he sleeps on a sofa bed in the cold conservatory whenever he can be persuaded to stay there.

Gosh. I am making her sound like the Wicked Stepmother I am not sure she is. Though I do not know her at all, and I am very aware of how much she resents my very existence, I also know that she is a woman just like me, who wants to ensure the security of her family. Who wants her husband and her baby to be her world. I do understand that. But I simply cannot tolerate her indifference to my little boy. As far as I am aware, she has never spent any time with him alone, does not ever go on Mark and Finn’s outings and has never bought him a single present, or item of clothing in the five years she has known him.

It barely seems possible to me. Finn is an extremely easy child to love. Heaven knows he talks too much, but he is impeccably behaved, has the sweetest, kindest heart and so desperately wants to love this woman who will not love him back. And for my part, though I think asking for her friendship is probably out of the question, I truly wish that I could call her when Finn isn’t feeling well. When I have forgotten to pack socks, so I could check that she has some spare ones for him. That I could be sure that she would not shake his hand when he says goodbye to her, but would instead embrace him in a great big, Step Mum hug.  I wish he went to a house where there was a room for him. A home from home. A wardrobe with clothes that belong to him in. I wish that occasionally she would shove shove his clothes into the washing machine instead of sending them home to me caked in mud. I wish, really, that she would be Finn’s Mum when I am not there to do it.

But this I know for sure: Finn will love his new little brother. And I will too because he is Marks. Because the love and respect that I have always showed Finn for Mark: the respect and love that still remains, will be extended to a baby called Sam, who must, I think, be just about the luckiest little fella in the world to have a brother like Finn…

Oh how my world is changing, Readers.