Fire Emblem Heroes: Daily Lives of the Heroes - Ch. 46 - Riddle

[MangaDex]

 

[ImperiumZero]

So...the answer is Cynthia?

 

[Arthran]

I don't get it, was there a joke here?

 

[Nolonar]

@Arthran
I'm not sure what the joke was supposed to be, but it was definitely a reference to Awakening.
"Changing the future" is the running theme of Awakening. "A certain father" refers to Chrom, and "a certain daughter" refers to Lucina (aka. Masked Marth).

Maybe the joke was that Lucina didn't realize Summoner was talking about her and her dad?