The closer in age siblings are, the more likely it is for them to spread lice to one another. Our statistics show that siblings get lice about 70% of the time when there is a lice infestation in the family. That’s because siblings close in age are likely to spend more time together and share rooms, hair accessories, and clothing that might carry hair with lice.Lice spread primarily through head-to-head contact. When siblings share a bed or bedroom, and one has head lice, others are likely to get lice, too. Lice don’t fly or jump, but if a louse is on a shaft of hair that falls on a jacket or hat or hair brush, it will crawl on the next head it can find in a matter of seconds.Lice can’t live anywhere but on a human head, so it is a matter of survival to get on the nearest head.Head lice have become more difficult to treat in recent years as so-called “super lice” have become the norm. These lice have developed a resistance to the chemical pesticides used in the most popular lice products. Research published in the Journal of Medical Entomology in 2016 found that 98 percent of lice in the United States are now immune to the pesticides used in lice removal products.