How did people address one and other in medieval times?

It depends of your country and if you were writing or talking to him.

King-Queen : Your Majesty and then Sir/e or Ma'am.

Duke-Duchess --> Your Grace ( His/Her Grace )

Marquis-Marquess --> My Lord Marquis/Marquess and then My Lord/Your Lordship

Earl --> The same as above

Pretty much the same for Baron, Viscount,...Etc

Check this http://en.wikipedia.org/wiki/Forms_of_address_in_t...

If you were for example, to talk to a French noble but in English, to talk to them with their respective title; For Example to a Duke and Duchess --> " Monsieur le Duc, Madame la Duchesse ".

So I think that, depending on the country or the character's nationality of your story, you should use their title in their language.

If you keep to English, then you should find all the information you need in the wikipedia link above.

Hope that helps!

As in the main royal children were not brought up by their parents but sent off to other noble families to be brought up they often didn't know their parents, if they met them they would be instructed to address them using their formal title, certainly not 'lady Mother'...... children until the lasy century were 'seen and not heard', meaning they were not generally in adult company at all apart from with their nannies or teacher..so it was not until the 1980s that things changed for royal children with Prince Charles and Diana and they knew their parents as parents...........

Elizabeth Stuart who was the second child and eldest daughter of James VI and I, King of Scotland, England and Ireland, and his wife Anne of Denmark born in Fife Scotland in 1596 during her early childhood she was placed in the care of Lord Livingstone and his wife, on moving to England in 1603 from Scotland she was placed in care of Lord Harrington at Coombe Abbey Warwickshire and spent ALL of the rest of her childhood mainly in Exton in Rutland another of Lord Harringtons homes/estates thankfully being there she escaped being kidnapped by the Gunpowder Plotters who attempted to kidnap her in 1605 and basically by 1612 her father had 'sold her off to marry 'Frederick V, Count Palatine of the Rhine by 1612. Lord Harrington accompanying her to her new home in Europe, she later became the Queeen of Bohemia http://www.exton.org/ scroll down and read "The rise and fall of the Harringtons and the Princess of Bohemia"

Reality of life for Royal/Noble children was no fairy tale, they were used as 'goods' to improve wealth, increase land and settle quarrels and females were thought of as a 'problem' to be married off as quickly as possible.

many ways depending on position, but it is not shown in case others are trying to penetrate the system as killers passing themselves off as friends, and whom may practice sacrifices