noun
stories from one's childhood
Refers to personal childhood memories or anecdotes, often told by an adult looking back.
祖母から聞いた幼物語は、今でも心に残っている。
The childhood stories I heard from my grandmother still remain in my heart.
noun
children's story; fairy tale
A story written for children, such as a fairy tale or folktale. Less common than 童話 or おとぎ話.
この幼物語は、小さな子供向けに書かれている。
This children's story is written for young children.
おとぎ話 specifically refers to traditional fairy tales or folk tales for children, while 幼物語 can be any story from or for childhood.
Compound of 幼 (osana, 'childhood') and 物語 (monogatari, 'story'). The exact historical derivation is uncertain, but the word is transparently formed from these elements.