My ex and I have been separated for two and a half years. I have a new partner and my ex has a new family. Our son has lived with me since the separation, and has not kept consistent visitation until he met his new partner in 2013 ( custody of children). My partner has had to move to New Zealand for work. I'm left living with my mother in her home as we can't afford two separate rents in two separate houses. What are the chances in family law of relocating to New Zealand with my four year old son?