Video report by ITV News reporter Martha Fairlie
Some 128,000 children in the UK will wake up homeless on Christmas day, the highest number in a decade, according to a housing charity.
Shelter's chief executive Polly Neate said the figure, which has jumped by two-thirds since 2011, is a "national scandal".
Many homeless families are put into temporary accommodation by local authorities, often sharing a single room with parents sleeping in the same bed as their children.
It can cause families "psychological turmoil", Shelter's report said, with children experiencing anxiety, shame and fear.
Several parents also said their child's mental and physical health had declined since they became homeless - citing bed bug infestations, broken heating, and stress.
Ellie, 15, told Shelter about the problems of living in a cramped room with her whole family.
She said: "It's hard to concentrate at school because there's the worry about coming home. It's just stressful.
"There's nowhere we can relax or get any privacy. Before it was much better.
"We had our own home right near school and right near our friends. We all had our own rooms and a cooker and a fridge. We could eat proper meals. I just want it to be like it was before."
Almost half of families in England placed into B&Bs stay beyond the legal six-week limit, the charity added.
Louis Williams, who lives with his family in temporary accommodation, shared with Shelter his letter to Santa.
It read: "Dear Santa, Please can I have a forever home. I don't want any new toys, I just want all of my old toys that are in storage and I would like my own lego bedroom with a desk to build my models.
"Everyone is sad living here and I just want us to be happy again."
The Shelter report comes amid the first sustained increases in child and pensioner poverty for 20 years.
Almost 400,000 more children and 300,000 more pensioners are living in poverty than four years ago, according to the Joseph Rowntree Foundation.
It's a national scandal that the number of homeless children in Britain has risen every year for the last decade. Many of us will spend Christmas day enjoying all of the festive traditions we cherish, but sadly it'll be a different story for the children hidden away in cramped B&Bs or hostel rooms. No child should have to spend Christmas without a home - let alone 128,000 children. >
Shelter said: "Most of us are unaware of how homeless children live. Families rarely experience the most visible symptom of homelessness - having to sleep rough.
"They are often embarrassed to even let relatives or friends see where they are having to live."
Responding to the report, a spokesman for the Department for Communities and Local Government said: "This government is committed to breaking the homelessness cycle once and for all, and is working with Shelter and others to do this.
"We're providing over £1 billion until 2020 to tackle the issue and are implementing the Homelessness Reduction Act - the most ambitious legislation in decades that will mean people get the support they need earlier.
"Councils have a duty to provide safe, secure and suitable temporary accommodation. This means that people are getting help now and no family is without a roof over their head this Christmas."
To support Shelter's Christmas appeal visit their website.