Hey Birte - maybe I have scurvy like the old sailors and pirates!
Naw, seriously, you could very well be right about a vitamin C deficiency here. I used to drink orange juice by the gallon, because I'm too lazy to peel oranges, but then I startet getting canker sores in my mouth and a friend of mine who's a pediatrician ( !!) said it could be the excessive acidity of the juice. So I quit altogether, but never bothered to replace that loss of daily vitamin C. I'm definitely going back to oranges and I'll get vitamin C tablets from the pharmacy tomorrow.
If your mother's poem is not too long and difficult to translate, I would sure love to read it.

Hugs
Teresa