@JeroenBaten @denisbloodnok
Thank you, and your daughter is, imho, amazingly right, and thanks for getting back on this.
Most vegans would say: take B12, but as it turns out, not everyone needs to. However, vegans usually scare away from saying that because people might be seduced to thinking they won't need supplements and fail to _check_ with their physisian/fail to get their blood work done. Also, supplementing B12 if you are a person who would not need is, is in no way harmful (it's not even expensive).
I would like to note that B12 deficiency is not uncommon in carnists and vegetarians. That's because our environment has become "too hygienic". This also goes for most farm animals. They get supplemented with B12 (some with cobalt so that they can produce more B12), and that's where carnists get their B12: they also consume supplements but those supplements have been filtered through an animal.