When?
The first thing my mother asked us when we announced we were engaged was when the ceremony would be, where we would have it if it would be muggle service or a wizarding service, or were we looking at both.
The same reaction as her mother.
My father had simply asked when this had happened, when we had gotten together in the first place, let alone when we'd gotten engaged. He'd had no idea that something was going on between her and me in the first place.
Her father just nodded and gave us his consent. Thankfully.
My sibling's reactions were wide an varied, but there was that question again. When? When did I propose, when we got together, when did we realise were in love. Ginny went over the top with her questions, taking Hermione off to the side so she could ask her more of her annoying questions, asking for details.
Only Ron didn't ask us when, he asked her why.