Bilingualism Matters resources for parents
Oasis database of short, accessible summaries about language development research
The ESRC International Centre for Language and Communication Development briefings for professionals
Small Talk for parents with lots of ideas to help communication, including some resources in Punjabi, Polish and Urdu, from the UKLA.
Talking Point from I CAN for parents and practitioners, with resources to understand and support speech and communication.
Tiny Happy People from BBC with lots of activities and advice to support communication, with the research behind the tips, and resources on pregnancy as well as little ones.
Hungry Little Minds, UK government campaign, with simple and fun activities for kids from 0-5 years.
You can find out more about multilingualism research going on at Cambridge Language Sciences