Include the text and we will add it to the card in an animated format like the example video (scroll right to see).  For example, you can write.  If you want to make your own animated message you can do it at a website such as

1.  Happy Birthday Mum, 
2.  You are the most wonderful mum in the world
3.  We all love you more than you could ever know
4. ???????
5. ????????????

We will create an animated message for you