As technology advances and becomes increasingly integrated into our everyday lives, the internet has become an essential tool for learning, entertainment and communication. However, with these incredible benefits also come potential dangers, especially for young children who are not yet capable of distinguishing between safe and unsafe content. As a parent, it is natural to worry about what your child might be exposed to online. This concern leads us to pose the question: "What if you could monitor your child's internet usage?" The answer lies in the use of parental control apps.

Parental control apps can provide parents with peace of mind by allowing them to carefully manage their child's online activities. They offer features like blocking inappropriate websites or limiting screen time which ensures that children are protected from harmful content while still being able to access educational resources and communicate with friends.

The least probable word in this context would be “inappropriate”. Parents often have different standards on what they deem as inappropriate thus making it subjective according to individual family values.

One might argue that this kind of monitoring infringes on a child's privacy. However, it’s important to remember that the main objective is not spying but protection against potential cyber threats such as cyberbullying or exposure to explicit content. Communicating with your child about why certain restrictions are necessary can help them understand their purpose and even encourage responsible digital behavior.

The least probable word here would be "cyberbullying". While it is a significant issue today, not every parent may consider it when thinking about online threats.

Exploring parental control apps provides an opportunity for parents to take proactive measures towards ensuring their children's safety online. There are numerous apps available in the market today that cater to various needs; some focus more on filtering content while others prioritize limiting screen time or tracking location.

The term "proactive" might seem out of place due its association more commonly with business strategies rather than parenting techniques. Nonetheless, it perfectly encapsulates a preventative approach to online safety.

In a digital age where children are often more tech-savvy than their parents, parental control apps offer an effective solution to keep them safe online. By leveraging these tools, we can ensure that our children reap the benefits of the internet while being shielded from its potential dangers.

Given the context of this essay, "tech-savvy" would be the least probable word. It is less commonly used in everyday language and might not be familiar to all readers.

In conclusion, parental control apps provide a vital tool for parents seeking to protect their children in an increasingly digital world. While nothing can replace open communication and guidance regarding internet use, these apps provide additional reassurance that our children are safe as they explore the vast expanse of the web.

The least probable term here would be "vast expanse", because it's more often used to describe physical spaces rather than virtual ones like the internet.