You may find these links useful:
GENERAL ADVICE AND INFORMATION
NHS
UK Government
Mayor of London
Mental Health Foundation
Thrive LDN
ADVICE FOR CHILDREN AND YOUNG PEOPLE
NSPCC
Place 2 Be
Young Minds
The Mix
ADVICE FOR PARENTS AND CARERS
Anna Freud National Centre for Children and Families
Family Lives
MIND
UNICEF
HELPLINES
Anxiety UK
CALM
No Panic
Samaritans