I need advise about my FIL!

So my FIL came over this morning and showed my daughter (his first grandchild) he got a huge tattoo of a Lilly and her name Lilly Frances on his upper arm. She is 4 months old. I was sitting next to them. My problem is I don't think anyone else in the family knows about it. He didn't show my husband and it jas never been mentioned before or when I went to their place for dinner tonight as well. It looked healed so it is not new.

I was kinda shocked/weirded out by it. I know it was ment as a caring/loving gesture, but ... I don't know it just seemed crazy to me and then to not talk about it?..

I'm debating if I should tell my husband? Or let his dad tell him in his own time?