In a blog update on her website
on Monday, Jill explained that August had "ended on a sad note for my extended family."
"Please do pray for our family," she added. "We are so thankful for God’s grace during difficult days."
Meanwhile, Jessa posted a sermon about adultery to her Facebook page.
"The gospel convinces us of something irresistibly true, and then transforms our desires for something new," she quoted. "That conviction and passion keeps us out of bed with someone who’s not our spouse and rejects a thousand other temptations."
However, some members of the Duggar extended family have taken a harder line against Josh.
After the disgraced former 19 Kids and Counting
star, who already admitted to molesting five young girls
as a teenager, checked into Reformers Unanimous faith-based rehab facility in Rockford, Illinois following his infidelity fallout, Jessa's father-in-law Michael did not hold back against "pretender" Josh in a blog post on Monday.
"With the name of God on his lips he lived a covert and extensive lifestyle of evil," Michael wrote in the scathing, lengthy essay. "While proudly saying things like, 'Our family is like the epitome of conservative values,' he was looking at porn and soliciting affairs. He took a job at the Family Research Council that exists to promote the traditional family, all the while undermining his own family by violating his marriage covenant. He flourished in the fame of his family and the success of their television show, all the while betraying their trust and Christian values."
Another family member told ET they hope Josh "gets broken in rehab."
"We love the Duggar family," said Tony Richardson, Director of Development at Reformers Unanimous, where ET has learned Josh is seeking treatment, though he declined to confirm Duggar was a patient. "Our hearts and prayers are with them."