What is a good Christening gift for my friend’s baby?

My friends’ baby is four months old and they invited me to her Christening (family and close friend). Not sure what type of gift I should give? Money? Children’s books??

I would say give a sling carrier if they don’t already have one, they are very useful and come in all sorts of colors. Also childrens books would be an awesome idea! my daughter loved them when she was 4 months!