My heart just goes out to the boys and of course Liam and her Family. It's just so so sad and again a seemly stupid tragedy.
That symbol is the Claddagh. Most people wear it as a ring. Usually when the heart is turned in towards your own heart it means that your heart is taken and pointing outwards means your heart is not taken. Lots of people of Irish heritage or Irish living abroad would wear the Claddagh Ring as a wedding ring or an engagement ring:
The ring has three distinct elements each with its own symbolism:
Hands - symbolising Friendship
Heart - for Love
Crown - signifying Loyalty