I was in a similar situation Alea, but that was many years ago.
I was taking our youngest son to his play school, where I got to know a lady who came from the same region in the UK, where I was brought up. So I knew her children but had never met her husband.
When going to collect my son I noticed her older child having his coat being put on by a man, who I thought looked the age to be the child's grandfather. So I stupidly remarked,
'Are you his grandfather?'
He turned his head with a smile and replied,
'No, I'm his father!'
Of course, all the apologies had to come out and we all did get on well.
How do you acknowledge Easter.