Do you have pets? (dogs? cats?) She may be one of those people who thinks of them as one's "children".....and meant the father's day meme in that context. ??????

I'd probably go with a simple "thank you". If you assume she means well then she would be hurt to know she had hurt you and sometimes you just suck it up.

It sounds like she wanted to do what little she could to support you at a time you might be feeling your loss strongly. It's difficult to say the right thing in sensitive situations.

How about something simple, yet heartfelt, like, “Thank you so much for thinking of me and my father today. It means a lot.” Or, if that's too strong, perhaps, “I appreciate your kindness.” And then maybe move on to something else so there's no reason for her to linger on the issue. I try to just accept that people are trying to be considerate when they send things like that, but it's hard sometimes to not be a little put off.

Remember the age old idiom, "Sticks and stones may break my bones but words will never hurt me".

If hurting her feelings is not an option, you must go with she means well. I don't know the context of the meme, but perhaps you could respond such that you appreciate her thinking of you, but also explain a bit about what makes you feel it's inappropriate. Again, I imagine the context has something to do with it. As an example, If losing your father so soon may make it sad or painful for you to reflect on this particular holiday, in the context of not having children to make it something celebratory, explain that. It's not impossible to be honest and kind.

Thanks for the fathers day meme but i have't been fortunate enough to have any kids yet...

maybe its one of those "thanks, i appreciate it, but....." kind of things.