It can be difficult to know what to do, and what to say when watching this happen to a friend. Some people worry they're being intrusive and tend to back off, whilst others don't want to upset the family by asking questions.
We spoke exclusively to Martin Ledwick, Head Information Nurse at Cancer Research UK, for an expert insight to the do's and don'ts when talking to a family that is being affected by childhood cancer.
Help with houseworkThe family are likely to be back and forth to the hospital so you could offer practical support such as helping to look after their other children or doing odd jobs for them like housework or shopping.
Listen to themHaving a child with cancer is incredibly frightening for a parent and they are bound to get sad and emotional at times. Offer to be there as a listening ear for them. It can feel hard and you may think you won't know what to say, but the main thing is just to listen and let them unburden their thoughts and worries. A hand on their arm and a listening ear can be much more helpful than words sometimes.
Be prepared to waitBe prepared for the long haul. Cancer treatment can take many months and your friends will need you every step of the way.
Offer liftsWhen they are tired and worried the last thing they'll want to do is drive, so offer to help give them lifts to and from the hospital.
Prepare some mealsTheir schedules will be very busy and they may have little time to cook proper healthy meals, so offer to cook a meal for them from time to time or make meals to go in their freezer so they don't have to rely on takeaways and fast food.
Speak to schoolIf they have other children, remind the parents to talk to their schools to let them know that the family are going through a difficult time. Brothers and sisters will get distressed too and might start to act out of character at school and need a little extra support.
Martin Ledwick, Head Information Nurse at Cancer Research UK, is supporting Cancer Research UK Kids & Teens, which funds research to find cures and kinder treatments for children's cancers. To find out more and sign up for a fundraising pack visit: www.cruk.org/kidsandteens