I hope that our friendship would be like that between xx and xx.
这里有一个逻辑的转换问题,没人能理解友谊怎么会像人,应该是像他们的友谊一样,所以一定要点出来的
I hope, the friendship between us is just like brother and sister.
I hope that our friendship will be like brother and sister.
或I hope that our friendship will be like sisters.
I hope that our friendship will be as close as that between xx and xx.