Hello Daddy, Where Are You?

Daddy is on a business trip and away for almost the whole week. This morning, while I was having breakfast, Zara reached for my mobile phone and started playing with it. I asked her "Why is Zara holding mummy's phone? Daddy calling is it?". She just smiled. I tooked the phone back and pretended to speak to its mouth piece "Hello, yes, she's here". I passed the phone back to Zara, and told her it's her call, daddy is on the line. She took it and put it near her ears, and started babbling. Aah, Pa, Ta. When she put the phone back down, I reminded her it's daddy, she should say hello to him. She took it back up, placed it near her ear, and started babbling again. This went on for a while. Well, if it's a real phone call, and she can actually hear the speaker on the phone, she'll normally push the phone back to me, and smiled sheepishly. I wonder why.