Andy Mitchell is pursuing a judicial review, saying the changes are discriminatory.
The Tony Blair Institute says people with conditions like anxiety should get employment support instead of cash benefits.
Charities say families are facing financial worries as changes to disability benefits come into effect.
Families on some benefits with three or more children will get an average rise of £4,100 a year.
The nine-year policy that capped financial help at two children has been removed.
Can Universal Credit and the work and benefits system more generally reshape itself to meet a new reality?
The scheme provides £500 to support low-income families welcoming a new baby in the London borough.
Pat McFadden says they would need a "good reason" to decline one of 55,000 new work placements.
Rising rents mean Steve Mikellides' housing allowance falls far short of covering his costs.
