After the resignation of Nawaz Sharif on July 28, hours after his disqualification from the Supreme Court, all eyes were on his younger brother, seen as a possible substitute.
The top court sacked him last month after an investigation into corruption allegations against him and his family, briefly plunging the nation into political uncertainty.
The wife of deposed prime minister Nawaz Sharif is to run for a seat in parliament, a lawmaker from Pakistan's ruling party said.
Kulsoom, who has been married to Sharif for 46 years, has largely stayed out of politics.
According to media reports, as many as 35 candidates have filed nomination papers for the by-poll scheduled to be held on September 17.
The roadshow via the iconic Grand Trunk Road, which links a large part of South Asia from Bangladesh to Afghanistan, came despite security threats and drew thousands of Sharif supporters on their way to the provincial capital of Punjab. "We were making progress and once again it has strangled", he told his supporters amidst chants of "wazir-i- azam Nawaz Sharif" (prime minister Nawaz Sharif).
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Within days of his departure, the ruling PML-N nominated former oil minister Shahid Khaqan Abbasi as a new prime minister, with the National Assembly approving the choice.
Asif Kirmani said Ms Nawaz submitted her nomination on Friday in the city of Lahore. "I was removed in a minute", he said. Sharif asked. To make sure that their vote is respected, he asked people to stand by him.
Nawaz also pledged his loyalty to the public and said that he would never betray them. Did I commit any kind of corruption?
Sharif, who could not complete his term for a third time, also asked the gathering, "Should I sit back and accept the verdict or fight the injustice?"
Mr Sharif added: "I want to ask why they ousted me".
The child, identified as Ahmad, was among a crowd of supporters gathered to greet Nawaz Sharif as his motorcade passed through Lalamusa.
Addressing a huge crowd in Gujranwala, he asked the people if they accepted the court decision against him and declared their "no" to be a referendum in his favour. "Promise me that you would do what I tell you", he said. "Wait for my call to join me in the struggle against such elements as have disgraced the democratic right of the people", he said.