TV personality Konnie Huq has said she trusts her sister to fight "tooth and nail" for local services as she takes over as Ealing Central & Acton MP.
Rupa Huq claimed the seat with 22,002 votes, previously held by Conservative Angie Bray who received 21,728 votes.
The new MP's sister and former Blue Peter and Xtra Factor presenter Konnie Huq said: "Rupa worked so hard on this campaign I just wanted to make sure I'd done my bit. I hit the phones and sent out emails to make sure as many people heard her story as possible
"She was the truly local candidate and now she's the truly local MP.
"Rupa loves Ealing & Acton and will stand up for residents at every opportunity - and she'll have to given the national results for Labour.
"I'm genuinely worried for the NHS, but I trust my sister to fight tooth-and-nail for local services just as she promised throughout her campaign."
In an email sent on May 6 to residents, Konnie had said her sister would be a fantastic Member of Parliament, having already served as Deputy Mayoress of the borough.
She told residents Ealing had been their home town since the 1960s, saying: "My two sisters and I were born, raised and schooled in the constituency. Now, as adults, we are all raising our own families here. We use the local schools and the NHS has now cared for three generations of our family."
She said she knew her sister would have a strong local voice and work tirelessly for local issues including protecting the NHS, improving employment rights, promoting sustainability and environmental issues, ensuring the building of affordable houses to get the next generation on the housing ladder, increasing job opportunities, and - she added - "the list goes on".
