It would mean we were stuck living in Australia for longer, potentailly until the child is 18. We had to (/chose to) move to Australia after the mother disappeard from the UK 5 years ago with our 6 month old child and Interpol found her in Australia. There was a 12 month international court case to return the child to the UK, but that fell through. So if I wanted my daughter to have a chance at having a father in her life, my only choice was to move to Australia and request the family court issue orders for contact and ideally shared care. 5 years on and we are still in and out of courts for child arrangelemts, domestic violence incidents etc.
If the mother doesn't receive citizenship she is not going to be able to afford to study here (which is her current plan) and that will increase the odds of her wanting to move back to the UK where both sides of our family live. Returning home would be a happy resolution for me to this awful few years. If Australia deem her to be of "good character" that would be anoher nail in the coffin for me, maybe it's none of my business whether they grant her citizenship or not, but I will definitely hurt.