Princess Catherine and her father in law King Charles have an incredibly close relationship but did you know that behind closed doors, Princess Catherine has a cute nickname for her father in law according to a courtier Princess Catherine calls Charles grandpa. The nickname is known for giving two affectionate names to his daughter in-law including Pii Bahu and Pii Bahu.

He reportedly always greeted her with a loving kiss while the couple always shared a close bond their relationship grew as they gave each other comfort during their ordeal The king visited Princess Catherine by her hospital bed while they were both in a clinic in London and the couple had a private lunch together in Windsor.

The day before she revealed her problem to the world in March it was very clear that he was very worried about her I think he wanted to make sure that if he could do something he would because for a young mother who was very fit and healthy it was different to having someone else deal with it in the 70s because I'm sure he was as much a comfort to her as she probably was to him.

Adding on I don't think it brought them closer together, he always had a lot of respect for his daughter-in-law, he thought she was wonderful, when everyone was in hospital. They didn't really want any fuss but the fact that the King was there, he was there and the Queen was with him and they went around checking on the princess and reassuring her, it was a reminder that the Windsors are just as human as we are.

We have to be very sympathetic to the fact that they are going through a whole other life problem, except that they have to go through it. It seems that Charles and Princess Catherine got off to a good start in 2010, when in the princess's official engagement interview with her now-husband, she spoke about how well her first meeting with the King had gone.