Kate helping to raise $4 million for the hospital where Prince George and Princess Charlotte were born

The Duchess of Cambridge is showing her gratitude for being "brilliantly cared for" by nurses and doctors at St. Mary's Hospital in London. To help the place where she gave birth to her two children, Prince George and Princess Charlotte, Kate has decided to give back by supporting the hospital's latest fundraising campaign.

The More Smiles Appeal, which was launched earlier this week by Imperial College Healthcare Charity and charity COSMIC, aims to raise at least $4 million toward a new children's intensive care unit.

The funds raised will help provide more beds, upgrade equipment and build a dedicated parents' room, among other facilities.

TAP FOR COMPLETE GALLERY"As someone who was so brilliantly cared for by St. Mary's, I am delighted to support the children's intensive-care appeal," said Kate.

"The thought of your child in an intensive care unit is harrowing for any parent," said Kate, who was last in the hospital in May for the birth of Princess Charlotte.

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"The commitment to expand and transform the children's intensive care unit at St. Mary's Hospital will vitally guarantee more space to treat more children and support more families.

"As someone who was so brilliantly cared for by St. Mary's, I am delighted to support the children's intensive care appeal, and commend the important work of all those involved in the project.''

The $4-million appeal will upgrade and extend the hospital's children's intensive care unit.

Each year, about 400 patients are cared for in the children's intensive care unit, but St. Mary's has to turn away hundreds more critically-ill children because it does not have enough beds. Last year, 233 youngsters weren't provided for, meaning were transferred hundreds of miles for treatment.

With the help of donations, the new unit will have 15 beds, almost doubling the current number, allowing more than 200 extra children to be cared for each year. There will also be a private room where doctors and nurses can provide emotional support to families whose children are seriously ill.

The unit specializes in treating serious infections in children, including meningitis and septicemia, as well as specializing in other life-threatening conditions such as seizures, asthma and sickle cell disease.

TAP HERE FOR GALLERYPrince George was also born at the Lindo Wing in 2013.

The appeal that Kate is supporting hopes to raise $4 million out of the $20 million needed. The remainder of the costs will be funded by Imperial College Healthcare NHS Trust and Imperial College Healthcare Charity.

"Our campaign will save more lives and help us give even better care to more critically-ill children and their families," said Dr. Simon Nadel. "We are most grateful for the Duchess of Cambridge's support and warm wishes."

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