Do you think that teachers should send home books with explicit Christian themes? I don't, nor would I support books with Jewish or Islamic themes.
The only role that parents have in a child's book is to die before the beginning (Snow White, Rapunzel, Cinderella) or during the story (Cinderella, Bambi, Nemo). They are not the point and stop trying to make it about them.
Every book I have seen with a same-sex couple aimed at that age group has been very much forced propaganda as opposed to a natural story. Natural stories do not have parents, because parents are boring. Parents are dead people who have gotten out of the way so our protagonist can have an adventure.
Consider the classic "Is Your Mama a Llama"? Is there room for same sex parents there? No, as there are no fathers in the story (as papa does not rhyme with llama).
If you want cringe, consider "Prince and Knight" It is a book about a Prince who does not want a princess, but is much more excited about meeting a cool knight. Somehow this is pathologized into the Prince being gay as opposed to just a regular chad who wants to hang with his bros. Any pre-tween boy would choose hanging with a cool knight over any girl (who almost certainly has cooties) but this book feels the need to suggest that this is "brave" and "stunning." Have the authors ever met a boy?
Prince & Knight
One of my daughter's favorite books!
https://www.amazon.com/dp/1499805527/ref=cm_sw_r_cp_apa_fabc_WXRVJVJB0Z34NEWS249X
Art is great too!