A paediatrician is warning parents to be careful of heat pumps when infants are sleeping in rooms heated by them.
Separate coronial inquests on Wednesday heard that that two children in Invercargill, aged nine months and 18 months, were put to sleep in rooms warmed by heat pumps.
Both were found dead the next day.
Barry Taylor of Otago University says the death of one of the children in particular was caused by a number of factors, including an infection, being left alone for 18 hours and overheating.
Professor Taylor says a safe temperature for babies is around 18 degrees but the temperature in that room was about 28.