Cory Monteith, who died aged 31 in a Vancouver hotel, was dating 'Glee' co-star Lea Michele.
In April, a representative for the Canadian actor said he was at a rehabilitation facility for an unspecified substance addiction.
Michele told People magazine at the time that she loved and supported her boyfriend and was proud he was seeking help.
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The actress attended the annual dinner dressed in purple and sporting a temporary tattoo in tribute to pop star Prince who died last month.
Charity says there has been a big rise in employees unfairly treating pregnant women and new mothers.
Sadiq Khan has said that his prospects of being elected London mayor could be damaged by the party's poor handling of racism accusations.