What's DNA got to do with being a parent?

It wasn't until I was expecting a baby to which I will have no genetic connection that I realised how obsessed we were as a culture with biological inheritance.

For example, how often do you hear phrases like:

• She looks just like you...
• Oh he doesn't look anything like his dad does he?
• Well they are your flesh and blood after all
• And blood is thicker than water...
• Oh he takes after his grandfather

I'm sure that I have uttered all of the above - which is shameful because apart from anything else they are all such unoriginal cliches (but I digress) - without even thinking about it. 

I know rationally that of course I will be bringing up mine and R's child as its mother - or Mama to be more precise. But, will I ever legitimately be able to see myself in him or her?

A friend recently reassured me about this, having been through the same experience. Indeed, I am sure many step parents can relate to this too, although the dynamics are different there again. She reminded me that ultimately a child's behaviour, outlook on life and future are down to their upbringing. Yes, there are genetic predispositions, but it will be my actions that will have every bit as much of an impact as R's.

One thing I never worry about is whether I will love my baby. Ten years ago I worked with children with special needs who needed respite care. It was a chance for them to get away from their parents, and a chance for their parents to have a breather. I remember one particular afternoon spending time with a boy of 12 who had very severe learning and physical disabilities. His communication consisted of being able to demonstrate that he was happy or not. I spent an afternoon watching television with him and trying to make him laugh. It was a couple of days before Christmas, and I remember very strongly feeling a real connection with him. His home life wasn't always as good as it might be, and I recall simply wanting to take him away from it all, and thinking how proud I would be of him were he my child. That had nothing to do with biology.