My iPhone 5S will not connect to Wi-Fi?

My iPhone 5S will not connect to my at home Wi-Fi. It always says unable to join! My MacBook Air, my moms phone, and my iPad are all connected to it! My sisters iPhone 4S will not connect either! I also have the latest software update 7.0.6.

Restart or reset your router and modem

You need to update through itunes you could better check for the softwares for Wi-Fi there.

Restart your modem, and remove all details of your home Wi-Fi that's saved in your mobile, now again search
and save your details with password, hopely it'll work.