Reasoning or 顶嘴?

At 婆婆's house 2 evenings ago, the munchkin was doing her favourite
exercise while waiting for papa to finish his dinner.

Me: Tricia, don't jump on the sofa. Remember last week in Nana's house,
you jumped on the bed and fell onto the floor?

Munchkin: (paused for a while to conjure up a reply) This is not a bed,
this is a sofa.

Should I laugh or should I cry???!!!!!!!