Depends how many children they have left in the country. I'm also a little in the dark about this as from what I can gather, under family sponsorship you can only sponser a lone parent (where their partner has either passed away or through divorce), where there are no children left in the home country, or the relationship with the remaining child(ren) in their country has broken down. I may be way out on this as its not a subject i've explored too much. On the NZIS website, there is a section under 'Family' about children sponsoring their parents, but, in true NZIS style, its pretty damn useless from what i've seen, but it may be worth digging a little deeper as I may well have skimmed over it a little quickly and missed something rather important.