I have a small business as a mobile catsitter alongside my day job and look after a good work colleague's cats quite regularly. He asked me at short notice to do a job recently, and when I went in the house I noticed sympathy cards on his mantelpiece. I looked at one and realised his mum had died, so I bought a sympathy card and left it in his kitchen. (I had googled his mum and her funeral details came up, and I realised that's where he was when he asked me to pet-sit.) He's paid me and messaged me to say thanks for catsitting, but not mentioned the card, and though that doesn't worry me I'm concerned I've overstepped the mark and embarrassed him. He's currently on compassionate leave but back later this week, and his Mum's funeral is in his work calendar for anyone to see. I don't want to have upset him.