Moving in a single cell to add text directly underneath existing text

[LisaAnn]

Hello,

Say I have one cell, name it A1.

Let say I have this:

I am LisaAnn.

How do I get "I am Blue's parent" directly underneath "I am LisaAnn" easily in that same cell A1?

So that it looks like this?

I am LisaAnn
I am Blue's parent

 

[AlanSidman]

After typing I am LisaAnn, press the Alt + Enter Keys simultaneously and then enter I am Blue's parent.