I wonder if you have already dealt (or is dealing) with something similar with your little one. I'm starting to notice it with my daughter now, who only wants to watch the "Elmo" video, read the "Mama Red Pajama" book, and sing the "Bumble Bee" song. It's so funny! And so typical at this age! Young children tend to like the same stories, the same food, the same videos, the same clothes, the same toys...

And the reason is very simple: kids like the same stories (or songs, or routines) because they like what is predictable - it releases the anxiety of not knowing what is going to happen. While you are reading them a familiar story, they feel safe and with a sense of control of the situation, since they know what is coming next. It's a short moment where they don't need to worry about being surprised by the unknown.
We are not aware of how unpredictable the world is for our little munchkins. Even having routine and consistency in their daily schedule, they are still surprised by new things all the time, such as the visit (or departure) of a family member or friend; a trip to a new place; the arrival of the holidays; the loss of a toy or a pet; having new food on the table; the change of schedule; the arrival of a newborn sibling; moving to a new house or even to a new bed; or saying "bye-bye" to the pacifier. You know, our little ones don't have a calendar and don't understand long-term schedules. Not even simple things such as the cycle of the weather, the sequence of the holidays, or the days when school is open or closed is always known to them. When they wake up in the morning, they usually don't know exactly how their day is going to be like: what they need to wear; who they are going to play with; if they will have to change beds or welcome another baby brother again; or even what food will be on the table for lunch. Will there be any guests for dinner again, like last night? Is today a weekday or a weekend? Is there school today? Will daddy be back from his trip? Is it my birthday yet?
No wonder they love repeating the same books and videos over and over again!! So, next time they ask for that, just smile and say "yes, my sweet pea". And allow them to have their little moment of predictability and sense of control over what is coming next.
Also, if possible, try talking with your little one about every plan in the family - even simple daily things. Let them know what you will have for dinner; tell them about the trip you are planning; talk about the friend who is moving out of town; show them on the calendar how far their birthday is; explain that they will have Halloween again next fall; share how the routine of that day will be like; explain that a new baby is coming (if you're pregnant); and even tell them if they are coming grocery shopping with you that day or not. Don't underestimate your child. Talk to them (use appropriate communication skills according to age). They are capable of understanding and they will appreciate knowing things ahead. And, please, if they ask, just read that same old book again!! :)
Thanks for reading! Please share comments or questions!