From the moment President Donald Trump was inaugurated, political journalist Molly Ball says Speaker of the House Nancy Pelosi presented herself as a formidable check to his power. She told him directly in a meeting of congressional leaders that his suggestion that he would have won the popular vote if not for millions of illegal votes cast in 2016 was an unequivocal lie.

Ball tracked Pelosi's lengthy and influential political career in a new biography, "Pelosi," and joined Boston Public Radio on Tuesday to discuss why she thinks the Speaker of the House is one of the greatest legislators of our time.

"Nancy Pelosi's reputation for toughness is well earned, and even Trump has at various times expressed respect for just her level of toughness and tenacity, which is a big part of what has enabled her to stay in politics for so long," said Ball.

Ball said Pelosi's experience as a mother taught her the "parallels between the selfish and egotistical nature of politicians and toddlers."

"She was by all accounts a quite exacting mother to her five young children, able to get them all to set the table for breakfast right after dinner was finished, making their own lunches, doing their own laundry," said Ball. "I think she learned a lot about keeping a large brood in line and disciplining them and getting them all to row in the same direction, which has been probably her biggest accomplishment as leader in the House, being able to keep that large and unruly Democratic caucus unified and in the right direction."

Molly Ball is TIME's national political correspondent.