Liberal Democrat leader Jo Swinson she was forced to call the police after a threat was made against one of her children.

The 39-year-old MP for East Dunbartonshire was seen to be upset in the Commons as she told Speaker John Bercow she had reported the incident.

She fought back tears as she raised a point of order, said: "I fear that the public watching today will perhaps take the view that the House does not take sufficiently seriously threats of violence."

It came as MPs discussed abuse and threats of violence they had received throughout the toxic Brexit debate.

The Commons Speaker John Bercow said: “I cannot overstate the frequency by which I have been informed over the last year or so by members on both sides of the House and on both sides of the Brexit argument of the fact and persistence of threats that they have received.”

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And responding Ms Swinson, he offered to meet members to hear their concerns.

Earlier in the Commons Brexit debate, Ms Swinson referenced her old son as she urged Boris Johnson to apologise for “misleading the Queen”, in a reference to the Supreme Court judgment that found that the Prime Minister acted unlawfully in suspending Parliament.

She said even the youngster knew he was to “say sorry” when he had done something wrong.

She said: "Even my five-year-old knows that if you do something wrong you have to say sorry. If my son can apologise for kicking a football indoors, surely the Prime Minister can have the humility to say sorry for misleading the Queen, the country, and illegally shutting down our democracy."

Last September she brought new baby Gabriel into the chamber during a debate on proxy voting.

She told the Commons: "We have had the Attorney General earlier today joke about wife-beating.

"We have had the Government asked if they would bring forward the domestic abuse bill now that Parliament has resumed and they dismissed those requests.

"And we had the comments...recalling Jo Cox and the threats that MPs face on a daily basis - and I may add that I today have reported to the police a threat against my child - that has been dismissed as 'humbug'."

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Attorney General Geoffrey Cox had earlier apologised to the House of Commons after MPs criticised the reference to domestic abuse.

Labour leader Jeremy Corbyn urged Commons Speaker John Bercow to bring together party leaders to agree a joint statement urging supporters to avoid abuse, which he warned could lead people to "threaten public representatives".

Commons leader Jacob Rees-Mogg, who has himself seen angry protests against his family home, said some MPs - "particularly women and ethnic minorities" - had been treated "in a quite disgraceful way."