Loohoo,
It is not uncommon for a virus to be passed around among family members. And, yes, it can recur in an individual that has had it previously.
It is difficult to not pass the virus in close quarters. But, proper hygiene can usually slow it down or irradiate it. It does not require much. Hand washing before and after touching a member who currently has the virus. Washing their clothing and bed linens frequently. Do not let children share toys (ill children should have their toys, well children should have theirs). Washing hands before touching food. Try not to touch your mouth or eyes.
According to the CDC, the simple act of hand washing is the single most important means of preventing the spread of viral and bacterial infections.
You should get several bottles of the alcohol based hand sanitizers. Put one in each room of the house. You can even get tiny bottles of the sanitizer that everyone can carry in their pocket. Encourage frequent use of the sanitizer.
Basically, you need to get the gastrointestinal (GI) virus out of the house. It is usually passed between people by skin to skin contact or coming in contact with sputum from coughing, sneezing, or vomiting. It can also be passed by contaminated food or utensils. Immediate washing after these contacts will help to irradiate the virus. Clean hard surfaces, such as kitchen and bathroom countertops, with an antibacterial cleaner.
Good luck. Hope everyone is feeling better soon.
Wishing you the best.