Domestic Chaplain to Royalty

[GUT]

Can anyone assist with what the requirements were to be appointed as domestic Chaplain to a Prince, and what duties would it entail.

I've got a couple in my tree. But they were clergy around Dorset and/or Devon.

I was once told that it was purely a methodology to provide someone who had found favour with the Royal Family with added income. But no idea how true that is.

[GUT]

Another question.

Most entries show one to be a domestic Chaplain, but when I look at the information for the Prince he is shown as a Royal Chaplain.