This isn't a favorite/favourite thing.
The person meant to accuse us of being deceitful. He/she meant to say that we were each a "liar."
But the individual spelled it lier...so either this person is a good speller who was saying that Iona and I are fond of reclining horizontally, or they were calling us deceitful and were spelling their insult of choice incorrectly...which is the case.
...unless they were from France, as you suggest...in which case they'd still be wrong, because then they'd be calling us a link, or a connection, which makes no sense and isn't worth discussing because the individual is most certainly not French or Dutch to begin with, and even if they are, and even though "lier" is technically a word, it isn't spelled the way they spelled it in the context they were trying to use it in, and a contextual misspelling is still a misspelling.