Oh wow! Thanks so much for all of the replies everyone. Your opinions are very much appreciated and it certainly has given me some food for thought!

I am inclined to agree with the overall consensus that whether siblings get on isn't so much about age gaps as it is about personality and the family environment in which they are raised. Especially when they are older, but I can see how small children with a close gap are much more likely to play happily together.

I do still need to consider my age though ie: being 35ish when TTC again if I wait til after I study.

What has bought this all to the fore for me is that i received a phonecall from the University midwifery course convenor yesterday out of the blue. And the more she told me about the course structure etc etc (it's a new degree for this particular uni) the more perfect it sounds. I also love the aspect of being able to do the latter part of my training and possibly then be employed by the Gold Coasts brand new first class University hospital which is due to open in 2011/12.
if I am successful in gaining a place in the first year offer round it will be very very hard to turn it down.