Selenium Eclipse Test Suite tests fail in the suite, but are successful when run individually

I have the following test suite to run an automation script to login to gmail then another script to click the Compose button:

TestSuite.xml

<!DOCTYPE suite SYSTEM "http://ift.tt/19x2mI9">
<suite name="Web Admin Tests" parallel="false">
<test name="BOS - Account Class">
<classes>
<class name="secondtestngpackage.GmailComposeEmail" />
<class name="secondtestngpackage.GmailLogin" />
</classes>
</test>
</suite>

When I run this test suite, the first test does not get passed the login screen in gmail, but the second test does, even though they reference the same functions. Is there a reason why this would happen? One test is able to enter the user id and password, since it is the second/last test, but when the first test is run, it is like the second test interferes with it, since its browser is now in focus.

GmailLogin.java:

 @BeforeTest
  public void launchBrowser() {
      ReuseFunctions.OpenApp("Chrome", "https://gmail.com");
  }

//Test 1:  Log into Gmail
  @Test(priority=1)
  public void LoginToGmailAccount() {

**GmailComposeEmail.java**

  @BeforeTest
  public void launchBrowser() {
      ReuseFunctions.OpenApp("Chrome", "https://gmail.com");

  }
  @Test(priority=2)
  public void LoginToGmailAccount() {

Reusable Functions File:

ReuseFunctions.func_EnterCredentials("username", "password");

        public class ReuseFunctions {

    public static WebDriver driver; 

/*Function 1:  Select Browser and Open Application Function
*/
    public static Object OpenApp (String Browser, String URL) {
        //Receive Browser Name Function
        Func_LaunchBrowser(Browser);
        //Receive Website and Open Function
        func_OpenURL(URL);
        return driver;
    }

    //Select Browser
    public static WebDriver Func_LaunchBrowser(String Browser) {
        String driverPath = "C:/EclipseJavaDev/";
        if(Browser=="Chrome"){
            System.out.println("launching chrome browser"); 
            System.setProperty("webdriver.chrome.driver", driverPath+"chromedriver.exe");
            driver = new ChromeDriver();
            }else if(Browser=="FF"){
            driver= new FirefoxDriver();
            }else if(Browser=="IE"){
            System.setProperty("webdriver.ie.driver", "Drivers\\IEDriverServer.exe");
            driver= new InternetExplorerDriver();
            }
            driver.manage().timeouts().implicitlyWait(80, TimeUnit.SECONDS);
            return driver;
            }
    //Open URL
    public static void func_OpenURL(String URL){
        driver.get(URL);
        driver.manage().window().maximize();
        }