What to give, what could be the best gift?

good day dear users steemit, my name is Slavik, I have a little problem! I have a friend whom I can call the best, A few days later, he and his wife celebrate the anniversary of their wedding, they invited me to their party, but I do not know what to gift in this case, when I started thinking about what to gift,I came to the conclusion that the theme of the gift for me is a very complex matter, after I turned for advice to people from a close circle it turned out that this is a difficult question not only for me. We together began to discuss the fact that always in us there were difficulties in choosing a gift, either for parents or for friends or even just for someone on the day of birth and in most cases this ends in that we just gave money as a gift, but from my experience of receiving gifts, I can say that I do not like very much when gift money, but for such a holiday, i think it is not appropriate in principle, because on my opinion, the anniversary of the wedding is more than just a holiday, I want to gift them something that they would remember this gift and he caused only warm memories.I want to ask you dear users!Advice from you:)Thank you