They joined the former Prime Minister's twins Carol and Mark at an emotional service held in St Paul's Cathedral, during which the iconic politician was hailed for her "leadership, courage and steadfastness."
The Very Reverend David Ison, Dean of St Paul's, began proceedings. "We remember the values by which she lived, the ideals she embraced, her dignity, her diligence, her courtesy, and her personal concern for the well-being of individuals.
"And as we remember, so we rejoice in the lifelong companionship she enjoyed with Denis, and we pray for her family and friends and for all who mourn her passing."
The Baroness's children had paid one final tribute to their mother, laying a card on her Union Jack-draped coffin which read, "Beloved Mother - Always in our hearts."
Her young granddaughter Amanda, 19, was visibly moved as she read a Biblical extract at the podium.
It was the Iron Lady's express wish that the teenager read at her funeral. David Cameron, above, was also requested by Mrs Thatcher and gave the second reading.
Before taking to the podium, the PM had said the funeral was "a fitting tribute to a truly great leader."
Mr Cameron's Chancellor George Osborne was moved to tears as Reverand Richard Chartres, the Bishop of London, eulogised the former Conservative leader.
He mentioned the policies that made her such a decisive figure, but concluded that it was a mother, grandmother and wife – not a politician – who was being laid to rest.
The front pews of St Paul's Cathedral were filled with leaders who strode the halls of Number 10 after the Thatcher era. John Major, Tony Blair and Gordon Brown all united to pay their respects.
"The storm of conflicting opinions centres on the Mrs Thatcher who became a symbolic figure - even an -ism. Today the remains of the real Margaret Hilda Thatcher are here at her funeral service.
"There is an important place for debating policies and legacy; for assessing the impact of political decisions on the everyday lives of individuals and communities.
"Parliament held a frank debate last week - but here and today is neither the time nor the place."
People from all walks of public life were among the 2,300-strong crowd, which included dignitaries from 170 countries.
David Cameron attended with wife Samantha, Sarah Ferguson was one of the first to arrive, and London Mayor Boris Johnson also paid his respects.
He told reporters the huge crowds that lined every mile of Baroness Thatcher's funeral route were "an astonishing comment on her power."
Earlier in the day, Baroness Thatcher left Parliament for the last time as her coffin began its journey from the Palace of Westminster to St Paul's Cathedral.
Ripples of applause swept through the rain-soaked streets of Central London as the funeral procession passed public mourners.
The sombre bells of St Paul's Cathedral pealed out through the air, stopping only when pallbearers had ended their slow, deliberate ascent inside.
Baroness Thatcher had rejected the expense of a state funeral – which wartime PM Winston Churchill was given as a final mark of respect.
The Iron Lady's swan song was a state funeral in all but name, however. To the untrained eye, she was seen off with all the pomp and circumstance one would expect for someone of her standing.
On Wednesay, Central London – and the world – gave pause to remember the political giantess who was the longest-serving British Prime Minister of the 20th century.