I'm friendly with his mother.

我和他的母亲很要好。

《柯林斯英汉双解大词典》

The little boy's mother taught him to be kind and friendly.

这个小男孩的母亲教他要善良和友好。

youdao

The children were very friendly with her and even thought of her as their own mother.

孩子们对她很友好甚至把她当成自己的妈妈。

youdao

He had never seen Jesus before, though his preacher-father and his mother often spoke with Him, and he knew Him as a friendly presence, unlike terrifying God.

ECONOMIST: Oral Roberts