Our twin children were only just four years old when we were sitting in our car at Larne, waiting to board the ferry for Cairnryan after a week visiting relatives in Newry, Co. Down.
A cattle truck pulled up beside us, crammed with cows who stared back at us and all the other motorists there, doe-eyed and innocent (the cows, not the motorists).
"Where are they going Mummy?" our daughter Rosina (above left) asked. "What are they going to do with them?"
"They are going to a farm," one of us replied.
"But they make beef from cows," she persisted. "Are they going to kill them?"
We don't believe in being dishonest with our children, so we told her that this was possibly the case. Although, we stressed, they could be milking cows.
Ignoring the latter possibility, Rosie was incredulous. "But can't we do something about it?"
"Like what?" I asked.
"Well let them go, or something. We can't just sit here and let them be taken away and killed, and not do anything. They haven't done anything wrong," she insisted, tears welling up in her eyes.
Some years later, shortly before her tenth birthday, I took Rosie on a shopping trip to Richmond. As we entered W.H. Smith's we passed a lady who was handing out leaflets. Inside the shop Rosie asked me what the lady had been doing. "Handing out leaflets," I replied.
"One of them had a little pig on it," she told me. "Do you mind if we go back and take one when we leave this shop?"
The leaflet was published by Viva!, an international vegetarian organisation, and featured a pig clearly suffering appalling treatment in the process of being prepared for slaughter. The text left nothing to the imagination. Rosie was quite distressed.
Typically, she joined the organisation and began to receive its literature. She declared herself to be a vegetarian, and has never eaten a meat product since. This was surprisingly easy for us to support - most restaurants and supermarkets offer a wide range of vegetarian options.
Before very long the whole family was being dragged along to an exhibition in Central London, where samples of vegetarian food were on offer and literature aplenty was thrust at us. One stall was run by an activist, whose name escapes me, who had been gaoled for animal rights activities. He was selling signed copies of his book in hardback.
Another was manned by a vegan group, and it was here that Rosie was horrified to learn that farm animals reared for dairy produce, even sometimes free-range, suffer all kinds of hardships as a result of the relentless demand for maximised production. It wasn't long before she made the decision to stop eating animal products completely and go vegan.
Now to those many people who tell us (and those who don't) that they think we are irresponsible parents for allowing a girl of Rosie's age to take a life-changing decision of this importance at her time of life, I would simply invite them to spend five minutes speaking - and listening - to Rosie. Having done so they would understand that her commitment to her cause is no passing junior enthusiasm. She is absolutely adamant that her conscience will not permit her to eat animal produce, and it has been our unenviable task to make it work.
Unlike vegetarians, vegans don't have it on a plate (no pun intended). Most restaurants and shops do not indicate whether their products are vegan and even the most innocent items need to be studied - sweets, for instance, will often contain gelatin whilst even vegetarian options such as Quorn more often than not include milk powder or free range egg.
With the assistance of supplements, and thanks to her penchant for calcium-fortified soya milk, Rosie maintains a healthy diet and consumes her required daily intake of protein, calcium, iodine and vitamins B12 and D, but it is always a struggle. As a lifelong carnivore it is an altogether alien experience for me, as well as for Caroline, trying to work out new and interesting recipes from such a limited range of options, although one unexpected by-product has been that we too find ourselves eating less meat.
As for Rosie's stubborn determination to stick to her guns in the face of all comers, one can only speculate as to where she gets that from.