Ah, damn, didn't catch that google double translation error, it has to be "we will promise the tall nephew". (French: Nous allons promettre le grand neveu.) So, yes, definitely talking about FWII here, as everybody's coming to visit for his engagement ceremony. And of course he isn't in love with the bride, but it's kind of telling that "cold" is really not how you'd describe his love life otherwise, but certainly Fritz' relationship with him.