Airport immigration with parent

Hello!

I'm bringing my mother to Japan for the first time in April and while I've been there several times already, it does bring up a few questions and I thought maybe someone of you has experience with that already.

My first question is probably a bit silly and I'd probably see it when I'm there anyway, but is it allowed to go together to the immigration desk? The one where they're checking the passport and take photos. My mother doesn't speak English well enough, so I'm worried she wouldn't understand questions being asked by the immigration officer. The last times I didn't get asked anything at all though, so I guess she'd managed alone.

Second question, for the customs declaration, you have to fill out one for families, but do we count as that if we're both adults? Probably sounds silly too, but I'm thinking of family tickets to zoos or train tickets where we'd both each need one. We do share the same family name.

Thank you for your help in advance already!

Both answers are YES.

Enjoy your trip to Japan!

Some airports actually request that families go to the same desk at the same time.