This question does not have a simple yes or no answer. First, you should consider what skills a family member will bring to the business. If a person has useful skills, it may be a good business decision to hire that person.
A related issue is whether you actually hire the family member or whether they might be offering some unpaid assistance on a specific topic or for a specific need. Paying family members for work-related tasks is a valid business expense, even when the family members are very young. Tasks such as emptying waste baskets, stocking paper, etc. are all valid business contributions. Such activities may help family members better understand the business and feel a part of it.
While positive aspects may be a result of hiring family members, there are reasons why it may not be a good idea. Family dynamics come into play. You as the manager must think about how existing family relationships might be helped or hurt by employing a family member.
One final consideration is where the family resides. Is the family member you are considering hiring a part of your household or a relative who is part of another household? Each of these scenarios offers a different set of positive and negative considerations.
In summary, hiring family members can be a positive experience or a negative one. You must consider how doing so might create tension in the family-business interface as well as within the separate family and business systems.