code: public static ExpectedCondition<WebElement> presenceOfNestedElementLocatedBy(
      final WebElement element,
      final By childLocator) {
  
      return new ExpectedCondition<WebElement>() {
  
        @Override
        public WebElement apply(WebDriver webDriver) {
          return element.findElement(childLocator);
        }
  
        @Override
        public String toString() {
          return String.format("visibility of element located by %s", childLocator);
        }
      };
    }
docs: An expectation for checking child WebElement as a part of parent element to be present
  
  @param element     used as parent element
  @param childLocator used to find child element. For example td By.xpath("./tr/td")
  @return subelement