Little Sister Graphic Novel or Original for 6 year old?

Hii, new to the subreddit and honestly bsc as a whole. My niece is 6 and I was wanting to buy her the first book of the little sister series. She’s just starting to read and I was wondering if you’d recommend the graphic novel or the regular novel for her?

I really want to foster her love of reading and thought these would be easy for her to get into. any other book recommendations welcomeee