子供でも

even a child

→ 子供
phrase Uncommon #13,238
even a child でも adds the meaning “even” to 子供 (child). Depending on the sentence, it can also mean that a child is acceptable or sufficient.
JA: 子供でも分かるくらい簡単な問題です。
EN: It's a problem that's easy enough for even a child to understand.

そんなこと子供でも知ってるよ

Even a child knows that.

子供でも理性があると考えられている

Even children are believed to possess reason.

この本は子供でも読めます

Even children can read this book.

子供でもいいだろ

Even a child would be fine, right?

— プラットフォーム (2019)

子供でも違いがわかるだろう

Even a child could tell the difference.

この本はやさしいので子供でも読める

This book is easy enough for even children to read.

この本は子供でも読めるほどやさしい

This book is easy enough for even children to read.

子供でもそれをすることができる

Even children can do it.

子供でも知ってる

Even a child knows that.

— 帰ってきたヒトラー (2015)

どんな子供でもその物語を楽しめる

Any child can enjoy that story.

子供でもそれぐらい答えられる

Even a child could answer that.