My five-year-old just finished 'reading' the one-year-old a book, in almost the exact words as it's written.
When I was her age it was Ernie and Bert's "I Can Do It Myself" (a.k.a. my personal motto at the time). For K, it's O Perníkové chaloupce, about Hansel and Gretel.
We bought the book for M's birthday, but it caught K's imagination somehow, and she loves me to read it to her and M both. She even insisted for a while that I pause in between sentences so she could repeat them after me.
I think it's good for her Czech, because most of the Czech children's books out there are either very simplistic (for babies, one or two words per picture) or else quite complex (for elementary age, lots of text, high vocabulary level and not many pictures). This is one of the few I've found that is in the middle, so it is accessible but still stretches K in terms of vocabulary and sentence structure.
For instance, she's asked me before about the sentences "Děti vzaly nohy na ramena" (an unfamiliar idiom) and "Tatínek hořce rozplakal" (crying 'bitterly'), and she 'read' them to M today. I also heard her use several other complex sentences or phrases from the book while reading - a level of language that, even when she interacts with the Slovak or me in CZ/SK, we just don't use in everyday conversation.
I know we need to read to her more in Czech, but as I've mentioned before, it's just hard to find suitable material. The other day the Slovak decided he wants to get in on the chapter book reading with a book in Czech (rather than Slovak, to help with Czech vocabulary). He decided on The Jungle Book (Kipling), because it was one of his favorites as a boy. I expect we'll give it a try someday soon.
For now, I'm just enjoying listening to my big girl reading to my little boy, neither one stopping to think that they're both learning something while doing it.