I think that they were all tought to paint when younger - by well known artists from what I have read - It was a skill expected of young, aristocratic ladies in the period. However only Ella and Empress Marie and Olga Alexandrovna seem to have carried on lessons into adulthood. You sometimes see paintings they have done and they are very good and a credit to their teachers. I'm sure I've seen some pictures of paintings done by Alexandra on postcards in watercolour for friends in the early years of her marriage and they were very good paintings, but I don't recall ever seeing an oil painting by her....but she did do embroidery and sold it for charity at various events.