Steadily, she described how from the moment Paul wakes, at 7am, until his bedtime, as late as 10pm, he needs constant care -- although he has a daily running route, he can't cross the road by himself. While he can shower, he can't pick appropriate clothes. He can't read, or write, or cook, and can only use the simplest appliances. If he hurts himself, sometimes he won't tell her, like last year when a hand injury went unnoticed overnight and landed Paul in hospital for three days.
"The only time I get a break is when he is on a run or asleep. It's hard work but I do it because I love him and want what's best for him.
"I could have placed Paul in residential care and had someone look after him," she said. "However I do not believe Paul would have achieved what he has achieved if it were not for my constant help ... and the fact he has been able to live with me in my home."
Ms Spencer's evidence also included her battle against authorities, which began with a letter to then Prime Minister Helen Clark in 2001, and has involved multiple agencies including the Ministry of Health and the Ministry of Social Development -- names she read while shaking her head.
She described the departments' responses to her as "unhelpful, obstructive and sometimes insulting".
Her efforts had been exhausting and at times humiliating, such as when she was mistakenly sent an email from officials saying she was "dragging poor Paul around like a teddy bear and telling the [Human Rights] Commission that she was a martyr".
A law passed under urgency on Budget Night in 2013 to stop her claiming compensation in the wake of another case was equally upsetting. She interrupted her testimony to look at the judge and say, "on Budget night! Budget night! For handicap people. Terrible".
Most insulting, had been the constant degrading of Paul's entitlements. There was only one assessment of his needs she thought was fair -- done by an official who spent five hours with the family and documented their every move. This was later overridden by a reviewer from head office, who slashed the entitlement despite never meeting Paul or herself.
"I do not accept the hours of care in that report," she said. The assessment said that if Paul was in residential care, he would get 58 hours of support. Ms Spencer pointed out the inequity in the policy, in that she provided a service just the same as those carers. "Except," she said, "unlike residential carers I do not have the luxury of clocking off at the end of the day. It is a 24/7 job."
Ms Spencer is seeking more than $200,000 in compensation, her claim dating back to the day of her first complaint in 2001.
Yesterday's case was the latest in a long battle, which she has won at court every step of the way.
Proceedings will continue with evidence from the Ministry of Health and the Human Rights Commission over the rest of the week.
Fight for Paul
2001: Margaret Spencer writes a complaint to then Prime Minister Helen Clark about the discrimination against family members caring for their disabled children, saying they should be paid the same as non-family carers.
2007: Ms Spencer repeats the complaint to the Human Rights Commission, which is already taking another similar case -known as the Atkinson proceeding.
2010: The Atkinson claim is upheld by the Human Rights Review Tribunal, finding that excluding payments to carers of disabled family members was discriminatory and in breach of human rights.
2012: The Court of Appeal upholds that decision after being challenged by the Ministry of Health.
2012: Margaret Spencer applies for family caregiver funding. The Ministry of Health refuses her.
2013: Ms Spencer seeks a judicial review of that decision. At the same time, a new Public Health and Disability Act is passed . The ministry says it precludes Mrs Spencer getting relief from review. That decision is also challenged by Ms Spencer.
2013: Chief High Court judge Justice Helen Winkelmann finds in Ms Spencer's favour, and says the ministry acted unlawfully and in breach of Ms Spencer's rights by refusing to consider her application for funding. She said Mrs Spencer was not precluded by the new Act from from applying for compensation for past discrimination. The Ministry of Health appeals.
2014: Margaret Spencer begins receiving payments of $14.25 per hour, for 29.5 hours a week, for Paul's care.
2015: Winkelmann's decision about compensation is upheld by the Court of Appeal.
2016: Margaret Spencer compensation case reaches the High Court.