It will save you energy, stress and time because you have a responsible and reliable photographer who documents your event. The work will be done faster. The photographs will look much better. In the long run, you'll earn more money with photographs that tell your story than it costs you to take them.
A professional photographer can give you a beautiful aesthetic that would otherwise be difficult to achieve. There's a reason why people flock to certain photographers who look amazing. They offer something unique and difficult to replicate by other means. You can have your own version of that beautiful photo you saw that caught your attention.
A good photographer will be able to provide images of your session that are consistent with the rest of their portfolio and, at the same time, give you something specific to your own family. They can take pictures in the same place, with the same light and similar postures, and still create a beautiful individual representation of their family, not something like “copy and paste”. Are professional photos worth it? Most photographers want a few hundred (USD) for the service. Some women told me that professional photos are discouraging, because it means that the guy either cared too much or wasn't social enough for organic photos to be taken.
Most photographers want a few hundred (USD) for the service. A professional photo of work or your educational program is one thing, but authenticity is lost when a profile is full of professional photos. I have spoken with many professional photographers and the most important opinion is that none of them can rely solely on their photography for a living.