''It was traumatic. No-one needs to go through that; we don't talk about it much.''
The book features a daschund, Poppy, and a foxy, Ted, who is aloof and out of control.
''Poppy teaches him about having a 'think-safe' brain,'' Ms Bremner said.
Targeted at children aged 5, the book advises such things as standing behind a tractor and blind spots.
''The main thing is it tells children to make good decisions and not to rely on safety gear.
''You can put it on but you can still be hurt.''
Ms Bremner is planning a follow-up book.
''I've had a couple of drafts written and there are some exciting things in the future.''
Al McCone, WorkSafe's engagement lead for agriculture, said three children had died on New Zealand farms in 2018 and agriculture continued to have a tragic number of on-farm fatalities.
''This needs to be turned around. We're encouraging farmers to make sensible decisions and be aware of the risks on the farm and Harriet's story is one way that families can connect with these actions.''
Ms Bremner had earlier written another children's book, Bob 'n' Pops, which told the story of an unlikely friendship between a rugged farm boy and his sausage dog.
-By Chris Tobin
Central Rural Life