Varadkar, who traces his roots to Varad in Malvan tehsil in Maharashtra's Sindhudurg district, is on a private visit to the country and arrived in Goa on Monday to ring in the New Year.
Danielle (28) was found raped and murdered in Canacona village in South Goa in March 2017, and a local youth Vikat Bhagat was arrested and is now facing trial in the district court.
Her mother Andrea Brannigan tweeted, "While enjoying in Goa Irish PM should discuss the rape/murder case of Irish national Danielle McLaughlin and why the trial is going far too slowly despite being fast tracked? Is very shameful if he doesn't do anything about it".
Brannigan had earlier met Varadkar in September last year with a set of demands, and had tweeted in September this year that they remained fulfilled.
She tweeted at the time, "One year ago today, I met @LeoVaradkar and he promised me changes. Well I am still sitting today in the same position they have only sent the embassy to Goa twice the rest of their promise didn't happen."
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